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Water Science and Engineering 2019年第3期12卷 213-220页

作者： Jun-hui Fan Xing-yu Liu Qi-yuan Gu Ming-jiang Zhang Xue-wu Hu GRIMAT Engineering Institute Co. Ltd. Beijing 101407 China School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China

The effect of hydraulic retention time (HRT) and pH on the biooxidation of ferrous iron during simulated acid mine drainage (AMD) treatment was investigated.The simulated AMD was highly acidic (pH 2.5), rich in iron (about 1700 mg/L) and copper (about 200 mg/L), and contained high concentrations of sulfate (about 4700 mg/L).The biooxidation of ferrous iron was studied in a laboratory-scale upflow packed bed bioreactor (PBR).The HRT was shortened stepwise from 40 h to 20 h, 13 h, and 8 h under the acidic environment at a pH value of 2.2.Then, the influent pH value was changed from 2.2 to 1.2 at a constant suitable HRT.Physiochemical and microbial community structure analyses were performed on water samples and stuffing collected from the bioreactor under different conditions.The results indicate that the efficiency of ferrous iron oxidation gradually decreased with the decrease of HRT, and when the HRT exceeded 13 h, ferrous iron in AMD was almost completely oxidized.In addition, the best efficiency of ferrous iron oxidation was achieved at the influent pH value of 1.8.Microbial community structure analyses show that Leptospirillum is the predominant genus attached in the bioreactor, and low influent pH values are suitable for the growth of Leptospirillum.

关键词： Acid mine drainage Iron-oxidizing bacteria Biooxidation of ferrous iron Hydraulic retention time Influent pH Microbial community analyses

Behavior of ductile steel X-braced RC frames in seismic zones

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Earthquake Engineering and Engineering Vibration 2019年第4期18卷 845-869页

作者： Eber Alberto Godínez-Domínguez Arturo Tena-Colunga Facultad de Ingeniería Universidad Autónoma de Chiapas Tuxtla Gutiérrez 29050 Mexico Departamento de Materiales Universidad Autónoma Metropolitana México City 02200 Mexico

A satisfactory ductile performance of moment-resisting reinforced concrete concentric braced frame structures (RC-MRCBFs) is not warranted by only following the provisions proposed in Mexico’s Federal District Code (MFDC-04). The nonlinear behavior of low to medium rise ductile RC-MRCBFs using steel X-bracing susceptible to buckling is evaluated in this study. The height of the studied structures ranges from 4 to 20 stories and they were located for design in the lakebed zone of Mexico City. The design of RC-MRCBFs was carried out considering variable contribution of the two main lines of defense of the dual system (RC columns and steel braces). In order to observe the principal elements responsible for dissipating the earthquake input energy, yielding mappings for diff erent load-steps were obtained using both nonlinear static and dynamic analyses. Some design parameters currently proposed in MFDC-04 as global ductility capacities, overstrength reduction factors and story drifts corresponding to diff erent limit states were assessed as a function of both the considered shear strength and slenderness ratios for the studied RC-MRCBFs using pushover analyses. Additionally, envelopes of response maxima of dynamic parameters were obtained from the story and global hysteresis curves. Finally, a brief discussion regarding residual drifts, residual drift ratios, mappings of residual deformations in steel braces and residual rotations in RC beams and columns is presented. From the analysis of the obtained results, it is concluded that when a suitable design criterion is considered, good structural behavior of RC-MRCBFs with steel-X bracing can be obtained. It is also observed that the shear strength balance has an impact in the height-wise distribution of residual drifts, and an important “shake-down” eff ect is obtained for all cases. There is a need to improve design parameters currently proposed in MFDC to promote an adequate seismic performance of RC-MRCBFs.

关键词： RC braced-frames seismic design nonlinear dynamic analyses steel-X bracing overstrength collapse mechanism story drifts residual drifts

Cu_(2)Si_(x)Sn_(1−x)S_(3) Thin Films Prepared by Reactive Magnetron Sputtering For Low-Cost Thin Film Solar Cells

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Chinese Physics Letters 2011年第10期28卷 274-276页

作者：颜畅刘芳洋赖延清李劼刘业翔 Departments of Metallurgical Science and Engineering Central South UniversityChangsha 410083

We report the preparation of Cu_(2)Si_(x)Sn_(1−x)S_(3) thin films for thin film solar cell absorbers using the reactive magnetron co−sputtering technique.Energy dispersive spectrometer and x-ray diffraction analyses indicate that Cu_(2)Si_(x)Sn_(1−x)S_(3) thin films can be synthesized successfully by partly substituting Si atoms for Sn atoms in the Cu_(2)SnS_(3) lattice,leading to a shrinkage of the lattice,and,accordingly,by 2θshifting to larger values.The blue shift of the Raman peak further confirms the formation of Cu_(2)Si_(x)Sn_(1−x)S_(3).Environmental scanning electron microscope analyses reveal a polycrystalline and homogeneous morphology with a grain size of about 200–300 nm.Optical measurements indicate an optical absorption coefficient of higher than 104 cm^(−1) and an optical bandgap of 1.17±0.01 eV.

关键词： technique analyses lattice

Radiotherapy-customized head immobilization masks:from modeling and analysis to 3D printing

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Nuclear Science and Techniques 2019年第9期30卷 103-118页

作者： M.A.R.Loja D.S.Craveiro L.Vieira E.Sousa J.A.Rodrigues R.J.F.Portal CIMOSM Centro de Investigacao em Modelacao e Optimizacao de Sistemas Multifuncionais ISEL IPL Instituto Superior de Engenharia de Lisboa Av. Conselheiro Emidio Navarro 1 1959-007 Lisbon Portugal LAETA IDMEC Instituto Superior Teccnico Universidade de Lisboa Av. Rovisco Pais 1 1049-001 Lisbon Portugal Department of Mechanical and Industrial Engineering Faculty of Science and Technology NOVA UNIDEMI Universidade Nova de Lisboa Caparica Portugal H&TRC -Health &Technology Research Center ESTeSL - Escola Superior de Tecnologia da Saude de Lisboa Av. D. Joao II Lote 4.69.01 1990-096 Lisbon Portugal Instituto de Biofisica e Engenharia Biomedica Faculdade de Ciencias da Universidade de Lisboa Lisbon Portugal

Immobilization devices may be a valuable aid to ensure the improved effectiveness of radiotherapy treatments where constraining the movements of specific anatomical segments is crucial. This need is also present in other situations, specifically when the superposition of various medical images is required for fine identification and characterization of some pathologies. Because of their structural characteristics, existing head immobilization systems may be claustrophobic and very uncomfortable for patients, during both the modeling and usage stages. Because of this, it is important to minimize all the discomforts related to the mask to alleviate patients’ distress and to simultaneously guarantee and maximize the restraint effectiveness of the mask. In the present work, various head immobilization mask models are proposed based on geometrical information extracted from computerized tomography images and from 3D laser scanning point clouds. These models also consider the corresponding connection to a radiotherapy table, as this connection is easily altered to accommodate various manufacturers’ solutions. A set of materials used in the radiotherapy field is considered to allow the assessment of the stiffness and strength of the masks when submitted to typical loadings.

关键词： Computed tomography 3D laser scanning Geometric modeling Head immobilization devices Stiffness and strength analyses 3D printing

Determining the spatial distribution of soil properties using the environmental covariates and multivariate statistical analysis: a case study in semi-arid regions of Iran

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Journal of Arid Land 2019年第4期11卷 551-566页

作者： Mojtaba ZERAATPISHEH Shamsollah AYOUBI Magboul SULIEMAN JesusRODRIGO-COMINO Department of Soil Science College of AgricultureIsfahan University of TechnologyIsfahan84156-83111Iran Key Laboratory of Geospatial Technology for the Middle and Lower Yellow River Regions College of Environment andPlanningHenan UniversityKaifeng475004China Department of Soil Science Agricultural Sciences and Natural Resources University of KhuzestanAhvaz***Iran Department of Soil and Environment Sciences Faculty of AgricultureUniversity of KhartoumShambat13314Sudan Instituto de Geomorfologia y Suelos Department of GeographyUniversity of MalagaMalaga29071Spain

Natural soil-forming factors such as landforms, parent materials or biota lead to high variability in soil properties. However, there is not enough research quantifying which environmental factor(s) can be the most relevant to predicting soil properties at the catchment scale in semi-arid areas. Thus, this research aims to investigate the ability of multivariate statistical analyses to distinguish which soil properties follow a clear spatial pattern conditioned by specific environmental characteristics in a semi-arid region of Iran. To achieve this goal, we digitized parent materials and landforms by recent orthophotography. Also, we extracted ten topographical attributes and five remote sensing variables from a digital elevation model(DEM) and the Landsat Enhanced Thematic Mapper(ETM), respectively. These factors were contrasted for 334 soil samples(depth of 0–30 cm). Cluster analysis and soil maps reveal that Cluster 1 comprises of limestones, massive limestones and mixed deposits of conglomerates with low soil organic carbon(SOC) and clay contents, and Cluster 2 is composed of soils that originated from quaternary and early quaternary parent materials such as terraces, alluvial fans, lake deposits, and marls or conglomerates that register the highest SOC content and the lowest sand and silt contents. Further, it is confirmed that soils with the highest SOC and clay contents are located in wetlands, lagoons, alluvial fans and piedmonts, while soils with the lowest SOC and clay contents are located in dissected alluvial fans, eroded hills, rock outcrops and steep hills. The results of principal component analysis using the remote sensing data and topographical attributes identify five main components, which explain 73.3% of the total variability of soil properties. Environmental factors such as hillslope morphology and all of the remote sensing variables can largely explain SOC variability, but no significant correlation is found for soil texture and calcium carbonate equivalent contents. Therefore, we conclude

关键词： soil properties remote sensing data topographical attributes multivariate statistical analyses geographic information systems land management

Elemental variations in glacier cryoconites of Indian Himalaya and Spitsbergen,Arctic

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Geoscience Frontiers 2017年第6期8卷 1339-1347页

作者： Shiv Mohan Singh Kumar Avinash Parmanand Sharma Ravindra Uttam Mulik Ajay Kumar Upadhyay Rasik Ravindra Earth System Science Organisation National Centre for Antarctic and Ocean ResearchHeadland SadaGoa403804India National Research Centre for Grapes Pune412307India Ministry of Earth Sciences Prithvi BhavanIMD CampusOpp.India Habitat CentreLodi RoadNew Delhi110003India

Cryoconite samples were collected from two different climatic domains i.e.,the Sutri Dhaka glacier,western Himalaya India and Svalbard glaciers,the Spitsbergen,Arctic,to understand the elemental source and elemental deposition patterns.The data of geochemical analysis suggest that the Himalayan cryoconite samples accumulate higher concentrations as compared to the cryoconite samples of the Arctic glaciers.The concentration of lithophile elements(Cs,Li,Rb and U)was recorded higher in the cryoconite holes of the Himalayas,especially,in the lower to the higher parts of the glacier,whereas,lower concentrations were recorded in the Arctic samples.Chalcophile elements in the Himalayan cryoconites are enriched in As and Bi while the Arctic cryoconite samples show a higher concentration of Bi,Pb and As.The higher concentrations are responsible for influencing the ecosystem and in human health related issues.Siderophile elements(Co,Fe,Mn and Ni)show high concentrations in the Himalayan samples,whereas,the Arctic samples show minor variations and low elemental concentration in these elements,respectively.In addition,a few elements,such as Ag,Mg,and Ca show higher concentration in the Himalayan glacier samples.Ca also occurs in high concentrations in Arctic glacier samples.R-mode factor analysis of the Himalayas(Arctic)samples indicate that the elements are distributed in four(three)factors,explaining 89%(90%)of the variance in their elemental distribution.The Factor 1 suggests statistically significant positive loadings for most of the lithophile,chalcophile and siderophile elements of the "Himalayan" and the Arctic cryoconite samples.The sample-wise factor score distribution shows a considerable variation in the sampling locations along the glaciers of both the regions.Factors 2 and 3,demonstrate insignificant loading for most of the elements,except statistically significant positive loading in some of the elements of the both,Himalayan and Arctic "cryoconites".The higher elemental concentration in the cryoconites of the

关键词： Cryoconite Elemental concentration Factor analyses Himalaya Spitsbergen

The improved FASTmrEMMA and GCIM algorithms for genome-wide association and linkage studies in large mapping populations

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The Crop Journal 2020年第5期8卷 723-732页

作者： Yangjun Wen Yawen Zhang Jin Zhang Jianying Feng Yuanming Zhang State Key Laboratory of Crop Genetics and Germplasm Enhancement Nanjing Agricultural UniversityNanjing 210095JiangsuChina Crop Information Center College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhan 430070HubeiChina

Owing to high power and accuracy and low false positive rate in our multi-locus approaches for genome-wide association studies and linkage analyses,these approaches have attracted considerable attention in plant and animal genetics.In large mapping population,however,fast multi-locus random-SNP-effect efficient mixed model association(FASTmrEMMA)and genome-wide composite interval mapping(GCIM)run a relatively long time.To address this issue,we proposed the improved FASTmrEMMA and GCIM algorithms in this study.In the new algorithms,some matrix identities,such as the Woodbury matrix identity,were used.In scanning each marker on the entire genome,in other words,the improved algorithms effectively replace the expensive eigenvector solutions in(restricted)maximum likelihood estimations in original algorithms with two(one)updated inner products and one updated vector-matrix-vector multiplication.Simulated and real data analyses showed that their computational efficiencies are increased sharply in large mapping population,although there are no mapping result differences between original and improved algorithms.In addition,the related software packages(mrMLM.GUI and QTL.gCIMapping.GUI)can be downloaded from the R and BioCode websites.

关键词： linkage matrix analyses

Integrity control of an RBMK-1500 fuel rod locally oxidized under a bounding reactivity-initiated accident

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Nuclear Science and Techniques 2019年第1期30卷 133-143页

作者： Hamid Boucherit Algirdas Kaliatka Azzedine Lounis Division of Fuel Technology Nuclear Research Center of Draria Lithuanian Energy Institute Science and Materials Engineering Laboratory University of Sciences and Technology Houari Boumediene

In 2007, the license for the second reactor unit of the Ignalina nuclear power plant was renewed considering the safety-related modifications introduced in this reactor.The Safety Analysis Report for this reactor unit was prepared with more strict criteria. The bounding reactivityinitiated accident(RIA) performed by the Lithuanian Energy Institute could be mentioned as an example. The performed analysis demonstrated that even when the worst initial conditions and possible uncertainties are considered,the fuel cladding remains intact. However, the analysis was performed assuming a fresh fuel assembly. In this study, an analysis of the fuel rod cladding behavior in the RBMK-1500 reactor following a bounding RIA is performed using the computational codes FEMAXI-6 and RELAP5. The analysis is extended by modeling an oxide layer(nodular corrosion) on the external surface cladding. An uncertainty and sensitivity analysis was performed using a method developed by the Society for Plant and Reactor Safety,employing the Software for Uncertainty and Sensitivity analyses, in order to evaluate the effect of the oxide layer on the inside and outside fuel rod temperatures. The results of the thermo-mechanical analysis(stress, strain, and enthalpy) for a local oxide layer with a thickness of 70μm show that despite the exceeded limit of allowed linear power density, the fuel rod is under acceptable safety conditions.

关键词： Safety Reactivity-initiated accident Corrosion RBMK-1500 FEMAXI-6 RELAP5 Software for Uncertainty and Sensitivity analyses (SUSA)

Screening for mutations in human cardiomyopathy- is RBM24 a new but rare disease gene?

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Protein & Cell 2019年第6期10卷 393-394页

作者： Anna Gaertner Andreas Brodehl Hendrik Milting Erich and Hanna Klessmann Institute Heart and Diabetes Center NRW University Hospital of the Ruhr-Udiversity Bochum Georgstrasse 11 32545 Bad Oeynhausen Germany

With great interest we have read the study of Liu et al.(2018) revealing the role of RNA binding protein 24 (RBM24) on global alternative splicing and dilated cardiomyopathy (DCM) in mice. As suggested previously, deficiency of Rbm24 causes embryonic lethality limiting the functional analyses (Yang et al., 2014). To circumvent this limitation the authors generated cardiac specific Rbm24 deficient mice and showed that homozygous deletion of Rbm24 at postnatal stage leads to rapidly progressive DCM and heart failure (Liu et al., 2018).

关键词： great interest study of Liu functional analyses

Evaluation of Dynamic Soil-Structure Interaction and Dynamic Seismic Soil Pressures Acting on It Subjected to Strong Earthquake Motions

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Journal of Shanghai Jiaotong university(Science) 2006年第4期11卷 530-536页

作者：车爱兰 IWATATE Takahiro 葛修润 School of Naval Architecture Ocean and Civil Eng. Shanghai Jiaotong Univ. Civil and Environmental Eng. Tokyo Metropolitan Univ.

In order to clarify the damage mechanism of the subway structure, the dynamic soil-structure interaction and the dynamic forces acting on the structure, a series of shaking table tests and simulation analyses were performed. The seismic response of the structure and the dynamic forces acting on the structure due to sinusoidal and random waves were investigated with special attention to the dynamic soil-structure interaction. The result shows that the compression seismic soil pressures and extension seismic soil pressures simultaneously act on the sidewalls, and big shear stress also acts on the ceiling slab due to horizontal excitation. The seismic soil pressure could be approximated to hyperbola curve, and reached a peak value with increase of the shear strain of the model ground. In addition, a slide and exfoliation phenomenon between the structure and the surrounding ground was simulated, using the nonlinear analyses. The foundation is provided for amending the calculation method of seismic soil pressure and improving the anti-earthquake designing level of underground structure.

关键词： subway structure dynamic seismic soil pressure dynamic soil-structure interaction shaking table tests dynamic analyses nonlinear characteristics