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Neoproterozoic basic magmatism in the southeast margin of North China Craton:Evidence from whole-rock geochemistry,U-Pb and Hf isotopic study of zircons from diabase swarms in the Xuzhou-Huaibei area of China

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Science China Earth Sciences 2012年第9期55卷 1461-1479页

作者： WANG QingHai YANG DeBin XU WenLiang international centre for Geoscience Research and Education in Northeast Asia Jilin University Changchun 130026 China College of Earth Sciences Jthn Untverszty Changchun 130061 China

This paper presents a synthetic U-Pb and Hf isotopic study of zircons and a whole-rock geochemical study on diabase swarms that were emplaced into the Proterozoic formations in the Xuzhou-Huaibei area,the southeast margin of North China *** from the diabase dykes display weak oscillatory zoning in the cathodoluminescence(CL) images and show high Th/U ratios(0.91-6.90),both of which are typical of a magmatic *** SHRIMP and Q-ICP-MS U-Pb zircon dating results indicate that the diabase swarms were emplaced at ca.890 *** isotopic analysis on these zircons gives Hf(t) values ranging from 2.26 to 14.74 and Hf model age t DM1 and t DM2 ranging from 843 to 1321 Ma and from 808 to 1779 Ma,***,the diabase swarms are characterized by a relative enrichment in LREE and LILE(Rb,Ba and La),a comparative enrichment in Cr and Ni,but a slight depletement in HFSE(Th,Nb,Ta,Zr and Hf).They are plotted in the within-plate tholeiite series on the tectonic discrimination *** together,these geochemical and isotopic data suggest that the primary magmas to form the diabase dykes in the Xuzhou-Huaibei area could have been derived from a transitional mantle in the Mesoproterozoic,and were most probably emplaced under a continental margin extensional setting at ca.890 *** results of this study demonstrate that the Neoproterozoic(800-900 Ma)magmatism was not restricted to the Yangtze Block,but also occurred at the southeast margin of the North China Craton.

关键词： diabase geochemistry zircon U-Pb dating Hf isotope Neoproterozoic Xuzhou-Huaibei area

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Investigation of changes in properties of water under the action of a magnetic field

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Science China(Physics,Mechanics & Astronomy) 2008年第11期51卷 1621-1632页

作者： PANG XiaoFeng1,2 & DENG Bo1 1 Institute of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu 610054, China 2 international centre for Materials Physics, Chinese Academy of Sciences, Shenyang 110015, China Institute of Life Science and Technology University of Electronic Science and Technology of China Chengdu China international centre for Materials Physics Chinese Academy of Sciences Shenyang China

The properties of water and their changes under the action of a magnetic field were gathered by the spectrum techniques of infrared, Raman, visible, ultraviolet and X-ray lights, which may give an insight into molecular and atomic structures of water. It was found that some properties of water were changed, and a lot of new and strange phenomena were discovered after magnetization. Magnetized water really has magnetism, which has been verified by a peak shift of X-ray diffraction of magnetized water + Fe3O4 hybrid relative to that of pure water + Fe3O4 hybrid, that is a saturation and memory effect. The properties of infrared and ultraviolet absorptions, Raman scattering and X-ray diffraction of magnetized water were greatly changed relative to those of pure water; their strengths of peaks were all increased, the frequencies of some peaks did also shift, and some new peaks, for example, at 5198, 8050 and 9340 cm?1, occurred at 25°C after water was magnetized. In the meanwhile, the magnetized effects of water are related to the magnetized time, the intensity of an externally applied magnetic field, and the temperature of water, but they are not a linear relationship. The study also showed a lot of new and unusual properties of magnetized water, for example, the six peaks in 3000–3800 cm?1 in infrared absorption, the exponential increase of ultraviolet absorption of wave with the decreasing wavelength of light of 200–300 nm, the frequency-shifts of peaks, a strange irreversible effect in the increasing and decreasing processes, as well as a stronger peak of absorption occurring at 50°C, 70°C and 80°C, the existence of many models of motion from 85°C to 95°C in 8000–10000 cm?1, and so on. These results show that the molecular structure of water is very complicated, which needs further study. Furthermore, the macroscopic feature of mechanics, for instance, surface tension force of magnetized water, was also measured. Experiments discovered that the size in contact angle

关键词： pure water magnetized water magnetic-field physical property spectrum saturation and memory effect mechanical feature surface tension force polarization angles of contact

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Efect of Varying Dzyaloshinskii–Moriya Interaction on the Bistable Nano-Scale Soliton Switching

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Communications in Theoretical Physics 2013年第12期60卷 658-662页

作者： L.Kavitha M.Saravanan V.Senthilkumar D.Gopi Department of Physics Periyar University The Abdus Salam international centre for Theoretical Physics Center for Nanoscience and Nanotechnology Periyar University Department of Chemistry Periyar University

The effect of Dzyaloshinskii-Moriya （D-M） interaction on the bistable nano-scale soliton switching offers the possiblity of developing a new innovative approach for data storage technology. The dynamics of Heisenberg ferromagnetic spin system is expressed in terms of generalized inhomogeneous higher order nonlinear Schr6dinger （NLS） equation. The bistable soliton switching in the ferromagnetic medium is established by solving the associated coupled evolution equations for amplitude and velocity of the soliton using the fourth order Runge-Kutta method numerically.

关键词： solitons magnetization reversal mechanisms perturbation theory exchange interactions

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Electrochemical anodization of cast titanium alloys in oxalic acid for biomedical applications

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Frontiers of Chemical Science and Engineering 2024年第1期18卷 13-24页

作者： Engie M.Safwat Soha A.Abdel-Gawad Madiha A.Shoeib Shimaa El-Hadad Restorative and Dental Materials Department National Research CentreGiza 12622Egypt Chemistry Department Faculty of ScienceCairo UniversityGiza 12613Egypt Central Metallurgical Research and Development Institute Helwan 11421Egypt

Titanium and its alloys have numerous biomedical applications thanks to the composition and morphology of their oxide *** this study,the colorful oxide films were formed by anodizing cast Ti-6Al-4V and Ti-6Al-7Nb alloys in a 10%oxalic acid solution for 30 s at different voltages(20–80 V)of a direct current power *** force microscopy was used as an accurate tool to measure the surface roughness of thin films on the nanometer *** electron microscopy and X-ray diffraction were performed to analyze surface morphology and phase *** to the results,the produced titanium oxide layer showed high surface roughness,which increased with increasing anodizing *** impact of anodizing voltages on the color and roughness of anodized layers was *** corrosion resistance of the anodized samples was studied in simulated body fluid at pH 7.4 and a temperature of 37℃ utilizing electrochemical impedance spectroscopy and the potentiodynamic polarization *** anodized samples for both alloys at 40 V were at the optimal voltage,leading to a TiO_(2) layer formation with the best compromise between oxide thickness and corrosion ***,findings showed that TiO_(2) films produced on Ti-6Al-7Nb alloys had superior surface roughness properties compared to those of Ti-6Al-4V alloys,making them more appropriate for orthopedic *** the obtained data and the fruitful discussion,it was found that the utilized procedure is simple,low-cost,and ***,anodization in 10%oxalic acid proved a viable alternative for the surface finishing of titanium alloys for biomedical applications.

关键词： DC anodization Ti-6Al-4V alloy Ti-6Al-7Nballoy oxidefilm corrosion

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Low Energy Ion Channelling in Single-Wall Nanotubes

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Chinese Physics Letters 2006年第8期23卷 2169-2171页

作者：郑里平许子健王呈斌朱志远朱德彰夏汇浩 Shanghai Institute of Applied Physics Chinese Academy of Sciences PO Box 800-204 Shanghai 201800 international centre for Material Physics Chinese Academy of Sciences Shenyang 110016

Monte Carlo simulation is used to study the low energy He ion channelling in a （17, 0） single-wall nanotube and its rope. The simulation shows that the channelling critical angle ψc = 48E^-1/2 （E is incident energy） for a 1.31-nm-diameter initial beam into the nanotube, while ψc = 45E^-1/2 for the 1.31-nm-diameter initial beam into its rope.

关键词： CHARGED-PARTICLES FIELD EMISSION CARBON diffraction CRYSTALS ATOMS

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A Trend towards a Stable Warm and Windless State of the Surface Weather Conditions in Northern and Northeastern China during 1961–2014

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Advances in Atmospheric Sciences 2017年第6期34卷 713-726页

作者： Bo SUN Huijun WANG Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and Technology international Pacific Research Center and Department of Atmospheric Sciences University of Hawaii at Manoa Nansen-Zhu international Research centre Institute of Atmospheric Physics Chinese Academy of Sciences

This study investigates the trends in the mean state and the day-to-day variability （DDV） of the surface weather conditions over northern and northeastern China （NNEC） during 1961-2014 using CN05.1 observational data. In this study, we show that the surface temperature （wind speed） has increased （decreased） over NNEC and that the DDV of the surface temperatures and wind speeds has decreased, indicating a trend towards a stable warm and windless state of the surface weather conditions over NNEC. This finding implies a trend towards more persistent hot and windless episodes, which threaten human health and aggravate environmental problems. The trends are also examined in reanalysis data. Both the ERA-40 and the NCEP data show an increasing （decreasing） trend in the mean state of the surface temperatures （wind speeds）. However, the reanalysis data show a consistent decreasing trend in the DDV of the surface weather conditions only in the spring. The underlying reason for the decreased DDV of the surface weather conditions is further analyzed, focusing on the spring season. Essentially, the decreased DDV of the surface weather conditions can be attributed to a decrease in synoptic-scale wave activity, which is caused by a decrease in the baroclinic instability. There is a contrasting change in the baroclinic instability over East Asia, showing a decreasing （increasing） trend north （south） of 40°N. This contrasting change in the baroclinic instability is primarily caused by a tropospheric cooling zone over East Asia at approximately 40°N, which influences the meridional temperature gradient over East Asia.

关键词： day-to-day variability surface weather condition trend northern and northeastern China

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Chromosome-level genome assembly of Oncomelania hupensis: the intermediate snail host of Schistosoma japonicum

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Infectious Diseases of Poverty 2024年第1期13卷 16-26页

作者： Qin Liu Lei Duan Yun-Hai Guo Li-Min Yang Yi Zhang Shi-Zhu Li Shan Lv Wei Hu Nan-Sheng Chen Xiao-Nong Zhou National Institute of Parasitic Diseases at Chinese Center for Disease Control and Prevention(Chinese Centerfor Tropical Diseases Research) NHC Key Laboratory of Parasite and Vector BiologyWHO Collaborating Centre for Tropical DiseasesNational Center for International Research on Tropical DiseasesNational Key Laboratory of Intelligent Tracking and Forecasting for Infectious DiseasesShanghai 200025People's Republic of China School of Global Health Chinese Center for Tropical Diseases ResearchShanghai Jiao Tong University School of MedicineShanghai 200025People's Republic of China School of Life Science Fudan UniversityShanghai 200438People's Republic of China CAS Key Laboratory of Marine Ecology and Environmental Sciences Institute of OceanologyChinese Academy of SciencesQingdaoShandong 266071People'sRepublicofChina

Background Schistosoma japonicum is a parasitic flatworm that causes human schistosomiasis, which is a significant cause of morbidity in China, the Philippines and *** hupensis (Gastropoda: Pomatiopsidae) is the unique intermediate host ofS. japonicum. A complete genome sequence ofO. hupensis will enable the fundamental understanding of snail biology as well as its co-evolution with theS. japonicum parasite. Assembling a high-quality reference genome ofO. hupehensis will provide data for further research on the snail biology and controlling the spread ofS. *** The draft genome was de novo assembly using the long-read sequencing technology (PacBio Sequel II) and corrected with Illumina sequencing data. Then, using Hi-C sequencing data, the genome was assembled at the chromosomal level. CAFE was used to do analysis of contraction and expansion of the gene family and CodeML module in PAML was used for positive selection analysis in protein coding *** A total length of 1.46 Gb high-qualityO. hupensis genome with 17 unique full-length chromosomes (2n = 34) of the individual including a contig N50 of 1.35 Mb and a scaffold N50 of 75.08 Mb. Additionally, 95.03% of these contig sequences were anchored in 17 chromosomes. After scanning the assembled genome, a total of 30,604 protein-coding genes were predicted. Among them, 86.67% were functionally annotated. Further phylogenetic analysis revealed thatO. hupensis was separated from a common ancestor ofPomacea canaliculata andBellamya purificata approximately 170 million years ago. Comparing the genome ofO. hupensis with its most recent common ancestor, it showed 266 significantly expanded and 58 significantly contracted gene families (P < 0.05). Functional enrichment of the expanded gene families indicated that they were mainly involved with intracellular, DNA-mediated transposition, DNA integration and transposase *** Integrated use of multiple sequencing technol

关键词： Schistosomiasis Schistosoma japonicum Oncomelania hupensis Chromosome-level genome

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Novel Sources of aus Rice for Zinc Deficiency Tolerance Identified Through Association Analysis Using High-Density SNP Array

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Rice science 2018年第5期25卷 293-300页

作者： Jae-Sung LEE Matthias WISSUWA Oscar B. ZAMORA Abdelbagi M. ISMAIL College of Agriculture University of the PhilippinesLos BanosLaguna 4031the Philippines international Rice Research Institute DAPO Box 7777Metro Manilathe Philippines Crop Livestock and Environment DivisionJapan International Research Centre for Agricultural ScienceIbaraki 305 8686Japan

Zinc （Zn） deficiency is a major soil constraint limiting rice crop growth and yield, yet the genetic control of tolerance mechanisms is still poorly understood. Here, we presented promising loci and candidate genes conferring tolerance to Zn deficiency and identified through association analysis using a 365 K single nucleotide polymorphism （SNP） marker array in a diverse aus （semi-wild type rice） panel. Tolerant accessions exhibited higher growth rate with relatively rare stress symptoms. Two loci on chromosomes 7 and 9 were strongly associated with plant vigor under Zn deficiency at a peak-stress stage. Based on previous microarray data from the same experimental plots, we highlighted four candidate genes whose expressions were accompanied by significant genotype and/or environment effects under Zn deficiency. Network-gene ontology supported known tolerance mechanisms, such as ascorbic acid pathway, and also suggested the importance of photosynthesis genes to overcome Zn deficiency symptoms.

关键词： aus genome-wide association study Zinc deficiency rice

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A STATISTICAL PREDICTION MODEL FOR SPRING RAINFALL OVER NORTHERN CHINA BASED ON THE INTERANNUAL INCREMENT APPROACH

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Journal of Tropical Meteorology 2012年第4期18卷 543-550页

作者：范可 Nansen-Zhu international Research centre/Key Laboratory of Regional Climate-Environment for East Asia Institute of Atmospheric PhysicsChinese Academy of Sciences

The spring (March-April-May) rainfall over northern China (SPRNC) is predicted by using the interannual increment approach. DY denotes the difference between the current year and previous years. The seasonal forecast model for the DY of SPRNC is constructed based on the data that are taken from the 1965-2002 period (38 years), in which six predictors are available no later than the current month of February. This is favorable so that the seasonal forecasts can be made one month ahead. Then, SPRNC and the percentage anomaly of SPRNC are obtained by the predicted DY of SPRNC. The model performs well in the prediction of the inter-annual variation of the DY of SPRNC during 1965-2002, with a correlation coefficient between the predicted and observed DY of SPRNC of 0.87. This accounts for 76% of the total variance, with a low value for the average root mean square error (RMSE) of 20%. Both the results of the hindcast for the period of 2003-2010 (eight years) and the cross-validation test for the period of 1965-2009 (45 years) illustrate the good prediction capability of the model, with a small mean relative error of 10%, an RMSE of 17% and a high rate of coherence of 87.5% for the hindcasts of the percentage anomaly of SPRNC.

关键词： spring rainfall over northern China statistical prediction model interannual increment approach

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Forest Cover Change Assessment in Conflict-affected Areas of Northwest Pakistan: the Case of Swat and Shangla Districts

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Journal of Mountain Science 2012年第3期9卷 297-306页

作者： Faisal Mueen QAMER Sawaid ABBAS Rashid SALEEM Khurram SHEHZAD Hassan ALI Hammad GILANI World Wide Fund for Nature(WWF)Pakistan LahorePakistan international centre for Integrated Mountain Development(ICIMOD) KathmanduNepal Asian Institute of Technology BangkokThailand

This study examines the spatial and temporal forest cover changes in Swat and Shangla districts to understand the deforestation pattern in context of the recent security conflict in these districts. We used multi-resolution satellite images to assess the long term deforestation from 2001 to 2009 and also to identify episodic forest cutting areas appeared during the conflict period of Oct. 2007 - Oct. 2008. There are only 58 ha of deforestation identified during the conflict period while 1268 ha of gross annual deforestation were assessed during last eight years. Most of the deforestation patches persist around the administrative boundaries at sub-district levels (tehsils) which can be attributed to ambiguity in unclear jurisdiction between the forest official. The results highlight that the forest cutting appeared in Swat and Shangla during the conflict period is not as significant when compared with the long term deforestation pattern in the area. On the one side the results of the study are supportive to the picture that emerges from international studies which report high rate of deforestation in the country and on the other side it negates any relation between the security situation and the increasing deforestation in the north western Pakistan. The study concludes that deforestation assessments require verification by independent sources of data, such as satellite imagery to improve our understanding of deforestation processes.

关键词： Forest cover change Deforestation Conflict-affected area GIS Pakistan

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