阳离子交换分离ICP/MS测定U_3O_8中的微量稀土元素

用硝酸溶解 U3 O8,通过阳离子交换柱 ,实现稀土元素与铀的分离。铀中的稀土元素回收率为 98%～1 0 6%。方法的检测限为 0 .1 ng/ g(3 σ,n=6) ,并讨论了分离条件、仪器参数的最优化选择及残留铀量对稀土元素测量的影响。

Exact Invariants and Adiabatic Invariants of Nonholonomic Variable Mass Systems

By the theory of symmetries and conserved quantities, the exact invariants and adiabatic invariants of nonholonomic variable mass systems are studied. The perturbation problem of symmetries for the nonholonomic variable mass systems under small excitation is discussed. The concept of high order adiabatic invariant is presented, and the form of exact invariants and adiabatic invariants as well as the conditions for their existence are given. Then the corresponding inverse problem is studied.

Analysis of the human Atox 1 homologue in Wilson patients

AIM: To analyze the metallochaperone antioxidant-1 (Atox1) gene sequence in Wilson disease patients. METHODS: Mutation analysis of the four exons of the Atox1 gene including the intron- exon boundaries was performed in 63 Wilson disease patients by direct sequencing. RESULTS: From 63 selected patients no mutations were identified after the entire coding region including the intron- exon boundaries of Atox1 were sequenced. One known polymorphism within the Atox1 gene (5’UTR -99 T>C) in 31 (49%) of the Wilson patients as well as one previously undescribed variation (5’UTR -68 C>T) in 2 of the Wilson patients could be detected. Statistical analyses revealed that the existence of a variation within the Atox1- gene showed a tendency towards an earlier onset of the disease. CONCLUSION: Based on the data of this study, no major role can be attributed to Atox1 in the pathophysiology or clinical variation of Wilson disease.

Geological analysis of gravitational rock slope deformation：a case from Nujiang River, China

This paper presents a study on the gravityinduced rock slope deformation observed along the Nujiang River in China. We performed a comprehensive field investigation and analysis to identify the deformation pattern of the slope and its triggering factors. Moreover, a geologicalevolutionary model was developed, and it considers the effects of river incision and rock mass degradation caused by weathering and simulates the mechanisms underlying the initiation and progression of the slope deformation. The results support the proposed failure mechanism in which fractures within the slope are induced by rock mass degradation caused by weathering. Importantly, the modeling reveals that compressional deformation at the toe of the slope results in a tensile failure in the upper portion of the slope, demonstrating that the rock mass in the slope toe is the key factor inducing slope deformation. This analysis of slope deformation and its spatial and temporal correlations with rock weathering and river incision reveal the main triggering factors that control the evolution of the studied slope and provide insights into the deformation process.

Phase Transition Analysis Based Quality Prediction for Multi-phase Batch Processes

Batch processes are usually involved with multiple phases in the time domain and many researches on process monitoring as well as quality prediction have been done using phase information. However, few of them consider phase transitions, though they exit widely in batch processes and have non-ignorable impacts on product qualities. In the present work, a phase-based partial least squares (PLS) method utilizing transition information is proposed to give both online and offline quality predictions. First, batch processes are divided into several phases using regression parameters other than prior process knowledge. Then both steady phases and transitions which have great influences on qualities are identified as critical-to-quality phases using statistical methods. Finally, based on the analysis of different characteristics of transitions and steady phases, an integrated algorithm is developed for quality prediction. The application to an injection molding process shows the effectiveness of the proposed algorithm in comparison with the traditional MPLS method and the phase-based PLS method.

Effects of Normalized Difference Vegetation Index and Related Wavebands′ Characteristics on Detecting Spatial Heterogeneity Using Variogram-based Analysis

Spatial heterogeneity is widely used in diverse applications, such as recognizing ecological process, guiding ecological restoration, managing land use, etc. Many researches have focused on the inherent scale multiplicity of spatial heterogeneity by using various environmental variables. How these variables affect their corresponding spatial heterogeneities, however, have received little attention. In this paper, we examined the effects of characteristics of normalized difference vegetation index （NDVI） and its related bands variable images, namely red and near infrared （NIR）, on their corresponding spatial heterogeneity detection based on variogram models. In a coastal wetland region, two groups of study sites with distinct fractal vegetation cover were tested and analyzed. The results show that： l） in high fractal vegetation cover （H-FVC） area, NDV! and NIR variables display a similar ability in detecting the spatial he- terogeneity caused by vegetation growing status structure; 2） in low fractal vegetation cover （L-FVC） area, the NIR and red variables outperform NDVI in the survey of soil spatial heterogeneity; and 3） generally, NIR variable is ubiquitously applicable for vegetation spatial heterogeneity investigation in different fractal vegetation covers. Moreover, as variable selection for remote sensing applications should fully take the characteristics of variables and the study object into account, the proposed variogram analysis method can make the variable selection objectively and scientifically, especially in studies related to spatial heterogeneity using remotely sensed data.

FEATURES AND MINING GEOLOGY SIGNIFICANCES OF THE COAL SEAM SLIP FOLD STRUCTURE IN XU-HUAI DISTRICT

In the analysis of some in-seam slip fold structures in the area of Xuzhou and Huaibei Districta it is noted that there exist some in-seam roof and footwall rock layers extremely incompatible to the existence of coal seams. Some of them are tbe slip fold structures that are wedged into coal seam by folding, but all of them are passively generated by in-seam shearing forces. In this paper, a discussion is put forward of the damage to coal seams by slip folds and the coal mining significance resulted from the study of slip fold structures.

Nonlinear creep damage model for soft rock under uniaxial compression

A nonlinear creep-damage model for soft rock under uniaxial compression waspresented,which takes into account both nonlinear creep and damage growth with time.The model is based on the hardening theory,The model is validated through comparisonwith experimental results.

Environmental Effects of Water Quality of Melendiz Stream and Mamasin Dam Site in Aksaray City in the Central Anatolia of Turkey

The main purpose of this study was to determine the changes in the water quality of Melendiz and Karasu streams, which recharge the Mamasin dam, and to evaluate its environmental impacts on the dam site that provides drinking water and irrigation demand in Aksaray city in the Central Anatolia of Turkey. The field researches were focused on estimating the main sources of contamination, determining and evaluating the changes in the water quality due to the direct wastewater discharges into the Melendiz and Karasu rivers, which recharge the Mamasin dam sites. During the study, water samples were collected from Melendiz and Karasu stream and Mamasin dam, and then, the physical and chemical analyses of water samples were conducted. The relevant in-situ and laboratory analyses were carried out during the dry and wet seasons. The results of the analyses showed that in term of the surface water quality criteria in terms of NO3-N value of both rivers and dam waters, the water quality is always considered as the 1st class in Melendiz stream, the 2nd class in Karasu stream and the 3rd class in Mamasin dam lake. Whereas, in terms of NO4-N values of both rivers and dam waters, the water quality is always considered as the 1st class in Melendiz stream, the 2nd-3rd class in Karasu stream. The total organic carbon （TOC） range for Karasu river is usually from 20 mg/L to 40 mg/L. The high value of organic matter in the Karasu stream can be explained by the availability of intensive green wetlands around this water resource. Finally, the Ministry of Forest and Water Authority give some suggestions for estimating protection zones of Melendiz stream and Mamasin basin＇s area, such as using the results of environmental tracers to investigate the agricultural contamination, including more sophisticated applications of multiple-tracer analyses to evaluate the travel time of contaminants and estimate the boundary of protection zones.

Strain analysis of buried steel pipelines across strike-slip faults

Existing analytical methods of buried steel pipelines subjected to active strike-slip faults depended on a number of simplifications.To study the failure mechanism more accurately,a refined strain analytical methodology was proposed,taking the nonlinear characteristics of soil-pipeline interaction and pipe steel into account.Based on the elastic-beam and beam-on-elastic-foundation theories,the position of pipe potential destruction and the strain and deformation distributions along the pipeline were derived.Compared with existing analytical methods and three-dimensional nonlinear finite element analysis,the maximum axial total strains of pipe from the analytical methodology presented are in good agreement with the finite element results at small and intermediate fault movements and become gradually more conservative at large fault displacements.The position of pipe potential failure and the deformation distribution along the pipeline are fairly consistent with the finite element results.

Multivariant statistical analysis for diagenetic information of chert from southern Tibet,China

There are large scale chert formations of different ages exposed widely in southern Tibet, along Yarlung-Zangbo suture zone. The typical chert specimens were sampled from Pengcuolin, Xialu and Zongzhuo profiles. Multivariate statistical analysis is applied for effectively extracting the geochemical information of the chert, and the raw data are processed by R-factor analysis. The first, second and third factors representing terrigenous, authigenic and hydrothermal constituents are extracted from the analysis results. From Pengcuolin, Xialu to Zongzhuo chert profiles, the variance ratios of continental and authigenetic factors become higher （ 51. 1% →62.9 % →91.6 % ）, while hydrothermal factor rapidly decrease （ 40. 9 % →32.2 % →0 ）. This tend- eney also present in the analysis for traee elements, indicating that Pengeuolin chert is hydrothermal origin, The Zongzhuo chert belong to normal sedimentation and the Xialu chert exhibit normal deposition interacted with hydrothermal sedimentation. The facts provide significant implications for understanding the diagenetic and palaeomineralization information of southern Tibet.

The Role of Harmattan in the Edaphic Processes in the Extreme-North-Cameroon

In the Cameroonian sudano-sahelian and sahelian zone, karal soils i.e., vertisoils and soils with vertic similarities largely spread on tropical black clay in depressions and fiat sectors. Those black cotton soils are out of season＇s sorghum loft, locally called as muskwari. As the staple diet in the Cameroonian dry areas, this crop becomes more and more an alternative to drying or better to climate changes. Till now, those soils are considered to be lacustrine or they are resulting just from weathering, according to pedologic researchs. The purpose of this communication, therefore, is to show the effects of Harmattan on the basis of our field＇s observations, investigations and superficial deposits＇ analysis： granulometry and diffractometry in the laboratory. Harmattan is a dry and stable air mass which originates from the saharian anticyclone. Its participation in edaphics process is very relevant. Indeed, dust storms take place throughout the dry season and vertisoil spreads out on various topographic locations bringing about homogeneity of texture and similarity of mineralogic spectrum. Their high kaolinite content, thin granulometric component （fine sand, silt and clay） are indicative of Aeolian loessial dust deposits. It could not be something else in this area of the most southern saharian blow of the great Saharo-Sahelian GWAS （global wind action system） in sub-equatorial latitudes, in line with the venturi formed by Ennedi and Tibesti mountains.

Multivariate Analysis in the Climate Change Studies and Water Quality of Lake Patzcuaro （Mexico）

In this study, the authors carried out the systemic analysis of water quality of Lake Patzcuaro in relationship with the climate change during a period of 85 years. The statistical comparison （medians, ＂t＂ Student test, regressions and correlations） for the precipitation, evaporation, observed temperature, minimum and maximum for the periods 1969-1988 （pre-impact） and 1988-2007 （post-impact） was realized. The ＂t＂ Student test for water quality during the period of 1981-2011, as well as, the regression analysis and multiple linear correlation of water quality from 2006 to 2011 were applied in joint way of the Cluster and Principal Component to observe the effects of climate change on water quality and vulnerability of Lake Patzcuaro. The comparative analysis of the meteorological data for 1921-1960 and 1973-2007 by the KOppen classification showed a climate change. The comparative Box Plots diagrams for 1973-1989 and 1989-2007, as well as, the ＂t＂ Student test, linear regression and correlation indicated significant changes in time for precipitation, evaporation, observed temperature, minimum and maximum （P ≤ 0.05）. The correlation and regression analysis indicated significant positive trends for turbidity, conductivity, total phosphorus, aluminum, oils and grease, in contrast with Secchi disk depth, transparency, Redox potential and dissolved oxygen concentration. The ＂t＂ Student test showed significant differences between 1981 and 2011 for transparency, hardness, alkalinity, conductivity, nitrite, and phosphate. Cluster and Principal Components of the physicochemical and biological of 2006-2011 confirmed the vulnerability of the system by human growth and climate change influence.

The uplifting and denudation of main Huangshan Mountains,Anhui Province,China

The Huangshan Mountain Geopark is an important geological landmark and tourist attraction.In this paper,we apply fission track dating to examine the uplift and exhumation processes that created the Huangshan Mountains and provide a timeline for their development.In addition to being an important scientific contribution,this information can be used on guided tours and to promote tourism.The results of eight apatite fission-track analyses suggest three age groups:56,45-30,and 15 Ma.These age groups are related to the uplifting-erosion processes involved in forming ancient multilevel denudation planes at 85-50,45-30,and 24-5 Ma,respectively.The scenic area has experienced three stages of thermal evolution.The first stage occurred before 80 Ma and the third stage after 13 Ma.The three stages had varying cooling rates:2.69,0.62,and 4.23°C/Ma,respectively.Uplifting rates also varied:0.08,0.02,and 0.12 mm/a.The uplifting ranges were also variable:1.14,1.57,and 4.00 km,respectively.Significant uplifting differences between diverse areas are obvious and there were four magnitudes of cumulative uplifting range:4060-3950,3760-3490,3190-3070,and 2650 m.The surface uplifting range varied from 450 to 2230 m.Denudation and uplifting amount averaged 2340 and 3400 m,respectively.The 1060 m difference between them is the average elevation at present.

Painlev Property, Bcklund Transformations and Rouge Wave Solutions of (3+1)-Dimensional Burgers Equation

Burgers equation is the simplest one in soliton theory, which has been widely applied in almost all the physical branches. In this paper, we discuss the Painleve property of the （3＋1）-dimensional Burgers equation, and then Becklund transformation is derived according to the truncated expansion of the obtained Painleve analysis. Using the Backlund transformation, we find the rouge wave solutions to the equation via the multilinear variable separation approach. And we aiso give an exact solution obtained by general variable separation approach, which is proved to possess abundant structures.

A mechanical model for the role of the neck linker during kinesin stepping and gating

In this paper, considering the different elastic properties in the attached head and the free head, we propose a physical model, in which the free head undergoes a diffusive search in an entropic spring potential formed by undocking the neck linker, and there are asymmetric conformational changes in the attached head formed by docking the neck linker to support the load force and bias the diffusive search to the forward direction. By performing the thermodynamic analysis, we obtain the free energy difference between forward and backward binding sites. And using the Fokker-Planck equation with two absorbing boundaries, we obtain the dependence of the ratio of forward to backward steps on the backward force. Also, within the Michaelis-Menten model, we investigate the dependence of the velocity-load relationship on the effective length of the junction between the two heads. The results show that our model can provide a physical understanding for the processive movement of kinesin.