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    题名 作者 年代 出处 被引量
1Edge Effect Correction in the S-A Method for Geochemical Anomaly Separation显示文摘Anomaly separation using geochemical data often involves operations in the frequency domain, such as filtering and reducing noise/signal ratios. Unfortunately, the abrupt edge truncation of an image along edges and holes (with missing data) often causes frequency distribution distortion in the frequency domain. For example, bright strips are commonly seen in frequency distribution when using a Fourier transform. Such edge effect distortion may affect information extraction results; sometimes severely, depending on the edge abruptness of the image. Traditionally, edge effects are reduced by smoothing the image boundary prior to applying a Fourier transform. Zero-padding is one of the most commonly used smoothing methods. This simple method can reduce the edge effect to some degree but still distorts the image in some cases. Moreover, due to the complexity of geoscience images, which can include irregular shapes and holes with missing data, zero-padding does not always give satisfactory results. This paper proposes the use of decay functions to handle edge effects when extracting information from geoscience images. As an application, this method has been used in a newly developed multifractal method (S-A) for separating geochemical anomalies from background patterns. A geochemical dataset chosen from a mineral district in Nova Scotia, Canada was used to validate the method.Ge Yong Department of Earth and Atmospheric Science, York University, Toronto, ON, M3J 1P3, Canada State Key Laboratory of Resources and Environmental Information System, Institute of Geographic Sciences & Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China Cheng Qiuming Department of Earth and Atmospheric Science, York University, Toronto, ON, M3J 1P3, Canada Earth Systems and Mineral Resource Engineering Lab, China University of Geosciences, Wuhan 430074, China Zhang Shenyuan Department of Earth and Atmospheric Science, York University, Toronto, ON, M3J 1P3, Canada Department of Resource and Earth Science, China University of Mining & Technology, Beijing 100083, China 2004Journal of China University of Geosciences2004,15,4:28
2Translation and Translation Studies: An Interview with Dr. Eugene Nida显示文摘In his recent interview, Dr. E. A. Nida briefly surveyed different schools of translation studies, exemplified his own ideas of the relationship between culture and translation, and commented on some of the controversial issues about translation studies.E. A. Nida 1, LIAO Qi_yi2( 1. 1865 Broadway, New York NY, 10023, U.S.A. 2. Sichuan Foreign Languages Institute, Chongqing, 400031,China) 2000外国语2000,23,3:20
3Sinobaatar gen. nov.: First multituberculate from the Jehol Biota of Liaoning,Northeast China显示文摘A multituberculate skeleton from the Lower Cretaceous Yixian Formation at Dawangzhangzi, Lingyuan City, Liaoning Province, Northeast China, provides new morphological information for early multituberculates. The specimen is the holotype of Sinobaatar lingyuanensis gen. et sp. nov. It has a narrow skull that lacks the superorbital crest or postorbital process. The dental formula is 3·?·5·2/1·0·3·2. The dental morphology, especially that of cheek teeth, of S. lingyuanensis is similar to that of Eobaatar, which places it in the family Eobaataridae. The postcranial skeleton of Sinobaatar is similar to that of other multituberculates. As in Holotheria, Metatarsal V of Sinobaatar articulates only with the cuboid and has no contact with the calcaneus, which probably represents the primitive condition of multituberculates. Nine carpals of Sinobaatar resemble those of Zhang-heotherium, except the centrale being larger than the trape-zoid. The dental features of Sinobaatar show again that eo-baatarids areHU Yaoming & WANG YuanqingInstitute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 10044, China American Museum of Natural History, New York, NY 10024, USA Biology Program (Ecology, Evolutionary Biology, and Behavio 2002Chinese Science Bulletin2002,47,11:17
4生态影响的人类驱动力足迹显示文摘尽管人为因素(人类作驱动力)被视为全球环境变化的关键作用因素,但关于这个问题仍存在很大的不确定性,甚至是矛盾的结论。我们试图通过估计两种人类驱动力(人口和财富)产生的众多全球环境影响,包括温室气体和臭氧损耗物质的排放以及生态足迹,来进一步阐明人为因素问题。人口使本文考察的所有影响程度加强,财富通常使环境影响增加,但是,特定影响取决于影响力的类型。这些调查结果重新将人口和物质财富视为对环境可持续构成威胁的主要因素,并对财富增加会带来环境影响改善的预言提出挑战。Eugene A. Rosa Richard York Thomas Dietz 宁恕龙(译) 周立志(校) 2004AMBIO-人类环境杂志2004,33,B12:17
5应用化合物组释放动力学方法评价银翘解毒片的释放特征(英文)显示文摘目的:考察中药化合物组释放动力学新理论在银翘解毒片释放特征评价中的适用性。方法:以Kalman滤波法为基础,进行紫外分光光度法测定银翘解毒片化合物组标准谱、线性、精密度、稳定性等方法学研究,测定银翘解毒片及其粉末的化合物组释放特征。结果:方法学结果表明,在0.112~1.120mg生药/mL范围内银翘解毒片化合物组呈线性相关(r=0.9997);高、中、低化合物组浓度测定的RSD分别为0.05%、0.07%和0.31%,浓度分别为0.278,0.556,和1.120mg生药/mL的供试液化合物组在24h内稳定。结论:化合物组释放度能简洁、可视、直观地反映银翘解毒片多组分释放动力学特征,中药化合物组释放动力学新理论可以定量地揭示传统中药制剂的新内涵或其给药系统的活性组分释放特征。陈立兵 王中华 傅丹丹 凌昳 葛卫红 顾景凯 YORK Peter 邵群 张继稳 2008中国天然药物2008,6,6:17
6ZnO nanofluids-A potential antibacterial agent显示文摘In this work, ZnO nanofluids were produced by a medium mill with a pH value of about 7.2 and characterized by Nano-Sizer and SEM. After milling, ZnO nanofluids were formed with an average particle size of 198.4 nm. The ZnO nanofluids used for testing were stored for different periods (1-, 90- and 120-day) and kept in different conditions (under the light and in the dark). The antibacterial activities of these ZnO nanofluids were evaluated by estimating the reduction ratio of the bacteria treated with ZnO. The results showed that the ZnO nanofluid stored for 120 days under the light had the best antibacterial behavior against Escherichia coli DH5a. SEM images suggest that an interaction between the ZnO particles and the E. coli bacteria cells caused by electrostatic forces might be a mechanism.Lingling Zhang Yulong Ding Malcolm Povey David York 2008Progress in Natural Science:Materials International2008,18,8:13
7Fractal and Multifractal Modeling of Hydrothermal Mineral Deposit Spectrum: Application to Gold Deposits in Abitibi Area, Ontario, Canada显示文摘A number of fractal/multifractal methods are introduced for quantifying the mineral deposit spectrum which include a number-size model, grade-tonnage model, power spectrum model, multifractal model and an eigenvalue spectrum model. The first two models characterize mineral deposits spectra based on relationships among the measures of mineral deposits. These include the number of deposits, size of deposits, concentration and volume of mineral deposits. The last three methods that deal with the spatial-temporal spectra of mineral deposit studies are all expected to be popularized in near future. A case study of hydrothermal gold deposits from the Abitibi area, a world-class mineral district, is used to demonstrate the principle as well as the applications of methods proposed in this paper. It has been shown that fractal and multifractal models are generally applicable to modeling of mineral deposits and occurrences. Clusters of mineral deposits were identified by several methods including the power spectral analysis, singularity analysis and the eigenvalue analysis. These clusters contain most of the known mineral deposits in the Timmins and Kirkland Lake camps.Cheng Qiuming Department of Earth and Atmospheric Science, Department of Geography, York University, Toronto, Canada M3J1P3 Faculty of Earth Resources, China University of Geosciences, Wuhan 430074 2003Journal of China University of Geosciences2003,14,3:13
8Experimental investigation of time-dependent cavitation in an oscillatory squeeze film显示文摘The occurrence of time-dependent cavitation and tensile stress in an oscillatory oil squeeze film were investigated experimentally. The test apparatus was a simple thrust bearing consisting of two parallel circular plates separated by a thin viscous oil film. During the test, one plate was at rest while the other (transparent) oscillated in a direction normal to its surface. This test configuration was chosen to avoid the rotational motion and complicated geometry of a squeeze film journal bearing. The frequency of oscillation was in the range of 5 to 50 Hz and was controlled by an electro-magnetic exciter. The process of cavity formation and its subsequent development was recorded by a high-speed video camera. Concomitant pressure in the oil film was measured both within and without the cavitation region. It was found that both tensile stress and cavities existed in a squeeze film under certain working conditions.CHEN Xiaoyang, SUN Meili, WANG Wen, D. C. SUN, ZHANG Zhiming & WANG XiaojingResearch Institute of Bearings, Shanghai University, Shanghai 200072, China Department of Mechanical Engineering, State University of New York at Binghamton, NY 13902-6000, USA 2004Science China(Physics,Mechanics & Astronomy)2004,47,z1:10
9The Faddeev knots as stable solitons: Existence theorems显示文摘The problem of existence of knot-like solitons as the energy-minimizing configurations in the Faddeev model, topologically characterized by an Hopf invariant, Q, is considered. It is proved that, in the full space situation, there exists an infinite set S of integers so that for any m ∈ S, the Faddeev energy, E, has a minimizer among the class Q = m; in the bounded domain situation, the same existence theorem holds when S is the set of all integers. One of the important technical results is that E and Q satisfy the sublinear inequality E ≤ C|Q|3/4, where C >0 is a universal constant, which explains why knotted (clustered soliton) configurations are preferred over widely separated unknotted (multisoliton) configurations when |Q| is sufficiently large.LIN Fanghua & YANG YisongCourant Institute of Mathematical Sciences, New York University, New York, New York 10012, U. S. A.School of Mathematics, Institute for Advanced Study, Princeton, New Jersey 08540, U. S. A. Department of Mathematics, Polytechnic University, Brooklyn, New York 11201, U. S. A. 2004Science China Mathematics2004,47,2:10
10Wear-resisting Oxide Films for 900℃显示文摘M.B.Peterson(Wear Sciences Corporation, Arnold, Maryland, USA)Shizhuo LI(Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110015, China)S.F.Murray(Rensselaer Polytechnic Institute, Thoy, New York, USA) 1997Journal of Materials Science & Technology1997,13,2:9
11Multifractal modelling and spectrum analysis: Methods and applications to gamma ray spectrometer data from southwestern Nova Scotia, Canada显示文摘Multifractal spectrum, autocorrelation/semivariogram and power spectrum are three dif- ferent functions characterizing a field or measure from different aspects. These functions are interre- lated in such that the autocorrelation/semivariogram and power spectrum are related to the low order statistical moments (0 to 2 nd) which may determine the local multifractality (τ ″(1)) of a multifractal measure. A better understanding of the interrelationships among these three functions is important because, on one hand, the multifractal modelling characterizes a multifractal measure in a more de- tailed manner since it involves moments of all orders. On the other hand, the commonly used semivariogram and power spectrum functions can be used as alternatives to study the dominant mul- tifractal properties around the mean measure. Moreover, semivariogram and power-spectrum func- tions provide spatial and spectral information, which is highly valued in geological applications. A new fractal relation found between area and power-spectrum will be useful for investigation of new meth- ods of spatial-spectral analysis for pattern recognition, anomaly separation, classification, etc. These results have been demonstrated with the case study of modelling gamma ray spectrometer data from the mineral district, southwestern Nova Scotia, Canada. The results have shown that the values of uranium (U), thorium (Th) and potassium (K) may possess monofractal properties whereas the ratios of these values show high multifractality. The values of the ratios U/K and U/Th show relatively large variances and may provide more information for distinguishing the distinct phases of the granites, country rocks as well as possible gold mineralization-associated regional hydrothermal alteration zones. In addition, the power spectra for U, Th, K, U/Th and U/K consistently show two distinct power-law relationships for two ranges of wave number 12≤ω ≤160 km and 0≤ω ≤12 km. These properties might provide useful thresholds for separating the power-spectrum values into two types of patterns to reflect different influences of possible geological processes such as hydrothermal altera- tion in the study area.CHENG Qiuming1,2 1. State Key Lab of Geological Processes and Mineral Resources, China University of Geosciences, Wuhan 430074, China 2. Department of Earth and Space Science and Engineering, Department of Geography, York University, 4700 Keele Street, Toronto, Ontario, M3J 1P3, Canada 2006Science China Earth Sciences2006,49,3:8
12Selection of Multifractal Scaling Breaks andSeparation of Geochemical andGeophysical Anomaly显示文摘Spatially superimposed multiple processes such as multiplicative cascade processes often generate multifractal measures possessing so-called self-similarity or self-affinity that can be described by power- law type of functions within certain scale ranges The multifractalities can be estimated by applying multifractal modeling to the measures reflecting the characteristics of the physical processes such as the element concentration values analyzed in rock and soil samples and caused by the underlying mineralization processes and the other geological processes. The local and regional geological processes may result in geochemical patterns with distinct multifractalities as wall as variable scaling ranges. Separation of these multifractal measures on the basis of both the distinct multifractalities and the scaling ranges will be significant for both theoretical studies of multifractal modeling and its applications. Multifractal scaling breaks have been observed from various multifractal patterns. This paper introduces a technique for separating multifractal measures on the basis of scaling breaks. It has been demonstrated that the method is effective for decomposing geochemical and geophysical anomalies required for mineral exploration. A dataset containing the element concentration values of potassium and phosphorus in soil samples was employed for demonstrating the application of the method for studying the fertilizer and yield optimization inCheng Qiuming Department of Earth and Atmospheric Science, Department of Geography, York University, Toronto, Ontario, Canada, M3J 1P3 2001Journal of China University of Geosciences2001,12,1:7
13Effects of Soil Fertility and Atmospheric CO_2 Enrichment on Leaf, Stem and Root Dark Respiration of Populus tremuloides显示文摘An open-top chamber experiment was conducted at the University of Michigan Biological Station near Pellston, Michigan, USA, to study the effects of soil fertility and CO2 on leaf, stem and root dark respiration (Rd) of Populus tremuloides. Overall, area-based day-time leaf Rd (Rda) was significantly greater at elevated than at ambient CO2 in high-fertility soil, but not in low-fertility soil. Mass-based leaf Rd (Rdm) was overall greater for high- than for low-fertility soil grown trees at elected, but not at ambient CO2. Nighttime leaf Rd. and Rdm were unthected by soil fertility or CO2, nor was stem Rda, which ranged from 1.0 to 1.4 μmol m-2 s-1 in the spring and 3.5 to 4.5 μmol m-2 s-1 in the summer. Root Rda. was significantly higher in high- than in low-fertility soil, but was unaffected by CO2. Since biomass production of P. tremuloides will be significantly greater at elevated CO2 while specific Rd will either increase or remain unchanged, we predict that carbon loss to the atmosphere through respiration from this ecologically important species would increase at higher CO2. Soil fertility would also interact with elevated CO2 in affecting the carbon flow in the plant-soil-air system.X. Z. WANG P. S. CURTIS and C. S. VOGEL Columbia University, Palisades, New York 10964-8000 (USA) The Ohio State University, Columbus, Ohio 43210-1293 (USA) University of Michigan Biological Station, Pellston, Michigan 49769 (USA) 2001Pedosphere2001,11,3:6
14Composite microcapsules with enhanced mechanical stability and reduced active ingredient leakage显示文摘Yue Long Kai Song David York Zhibing Zhang Jon A. Preecea 2016Particuology2016,14,3:6
15Fractal Correction of Well Logging Curves显示文摘It is always significant for assessing and evaluation of oil bearing layers, especially for well logging data processing and interpretation of non marine oil beds to get more accurate physical properties in thin and inter thin layers. This paper presents a definition of measures and the measure presents power law relation with the corresponded scale described by fractal theory. Thus, logging curves can be reconstructed according to this power law relation. This method uses the local structure nearby concurrent points to compensate the average effect of logging probes and measurement errors. As an example, deep and medium induced conductivity (IMPH and IDPH) curves in ODP Leg 127 Hole 797C are reconstructed or corrected. Corrected curves are with less adjacent effects through comparison of corrected curves with original one. And also, the power spectra of corrected well logging curve are abounding with more resolution components than the original one. Thus, fractal correction method makes the well logging more resoluble for thin beds.Li Qingmou Cheng Qiuming Institute of Geology & Geophysics, Chinese Academy of Sciences, Beijing 100101 Department of Earth and Atmospheric Science, York University, Toronto, Ontario, Canada, M3J 1P3 2001Journal of China University of Geosciences2001,12,3:5
16STIRPAT, IPAT and ImPACT: analytic tools for unpacking the driving forces of environmental impacts显示文摘Richard York Eugene A Rosa Thomas Dietz 2003Ecological Economics2003,,3:5
17Ceramide induces release of mitochondrial proapop-totic proteins in caspase-dependent and -independent manner in HT-29 cells显示文摘In this study, the release of mitochondrial proapoptotic intermembrane space proteins induced by ex-ogenous C2-ceramide in human colon carcinoma (HT-29) cell line was investigated. HT-29 cells were treated with 12.5, 25 and 50 μmol/L C2-ceramide in vitro. Flow cytometer was used to detect the mito-chondrial membrane potential (ΔΨm). Subcellular fractions were extracted by Mitochondrial/Cytosol Fractionation Kit after C2-ceramide treatment for 24 h. SDS-PAGE was used to determine the level of cytochrome c (Cyt c), high temperature requirement A2 (HtrA2) and second mitochondrial-derived ac-tivator of caspases (Smac) released from mitochondria, the expression of X-linked inhibitor of apop-tosis protein (XIAP) and caspase-3 for 24 h. The results showed that ΔΨm began to decrease from 6 h after 25 and 50 μmol/L C2-ceramide treatment (P<0.05) and cyclosporin A (CsA) could inhibit the col-lapse of ΔΨm through regulating mitochondrial membrane permeability transition pore. There was no effect of C2-ceramide on the expression of Cyt c, HtrA2 and Smac in the total levels. 12.5, 25 and 50 μmol/L C2-ceramide could induce Cyt c, HtrA2 and Smac to release from mitochondria to cytosol and down-regulate the expression of XIAP (P<0.05). Also there was expression of cleaved caspase-3 with C2-ceramide treatment. After the treatment with caspase inhibitor, C2-ceramide still induced the release of Cyt c and HtrA2, but Smac did not. Therefore, C2-ceramide could induce apoptosis of HT-29 cells through the mitochondria pathway. The release of Cyt c, HtrA2 and Smac from mitochondria did not occur via the same mechanism, the release of Cyt c and HtrA2 was caspase-independent and the re-lease of Smac was caspase-dependent.ZHANG XiaoFeng1, LI BaiXiang1, ZHANG Yang1 & LIU JiaRen2 1 Public Health College, Harbin Medical University, Harbin 150081, China 2 Department of Food Science, Cornell University, New York 14853-7201, USA 2008Science China(Life Sciences)2008,51,1:5
18Quantum dynamics study for reaction of H_2 + OD→H + HOD显示文摘TIME-dependent (TD) quantum wave packet theory, with a relatively small amount of computational effort, has been widely used in quantum dynamics calculation of atom and molecule reaction scattering. Many computational scaling advantages of the TD method can be found apparently in polyatomic system. In this note, by using the TD quantum wave packet method with the potential-averaged 5D model (PA5D), we give the calculated results of reaction probabilities, cross sections and rate constants for the H2 + OD reaction. The energyprojection method is used to transform the TD wave function into the TI (energy-indepen-ZHANG Yici, ZHANG Yanbing, ZHANG DeshengZHANG Qinggang, Dong H. Zhang and John Z. H. Zhang1. Department of Physics, Shandong Teachers University, Jinan 250014, China 2. Department of Chemistry, New York Uni versity, New York 10003, USA 1997Chinese Science Bulletin1997,42,2:4
19On conformal measures for infinitely renormalizable quadratic polynomials显示文摘We study a conformal measure for an infinitely renormalizable quadratic polynomial. We prove that the conformal measure is ergodic if the polynomial is unbranched and has complex bounds. The main technique we use in the proof is the three-dimensional puzzle for an infinitely renormalizable quadratic polynomial.HUANG Zhiyong~1 JIANG Yunping~(2,3) & WANG Yuefei~3 1. School of Information,Renmin University of China,Beijing 100872,China 2. Department of Mathematics,Queens College,City University of New York,NY 11367,USA Department of Mathematics,Graduate School,City University of New York,New York,NY 10016,USA 3. Academy of Mathematics and Systems Science,Chinese Academy of Sciences,Beijing 100080,China 2005Science China Mathematics2005,48,10:4
20Nitrite-derived nitric oxide by xanthine oxidoreductase protects the liver against ischemia- reperfusion injury显示文摘It was demonstrated that xanthine oxidoreductase (XOR), during ischemia, catalyzes the formation of nitric oxide (NO) from nitrite (NO2-) and this NO2--derived NO protects the isolated perfused rat heart against the damaging effects of ischemia-reperfusion (I/R) when conventional nitric oxide synthase (NOS) -dependent NO production is impaired. Liver is one of the organs with the highest XOR concentration. This study was designed to determine whether NO2--derived NO by XOR protects liver against I/R injury in vivo. For its minute amounts and active reactivity, NO can not be detected directly in real time in vivo by this time. We have to prove the above hypothesis indirectly. METHODS:Wistar rats were pretreated with saline, NOS inhibitor L-NAME (10 mg/kg intravenously), XOR inhibitor allopurinol (1.5 mg/kg orally), L-NAME +allopurinol and NO scavenger carboxy-PTIO (0.6 mg/kg intravenously) respectively (12 animals per group). And then, they were subjected to total liver ischemia for 40 minutes followed by reperfusion. Blood samples and liver tissues were obtained for analysis after 3 hours of reperfusion. Survival was also investigated. RESULTS:Allopurinol-treated animals exhibited further increased serum alanine aminotransferase (ALT) levels and liver myeloperoxidase (MPO) activities, but further decreased liver adenosine triphosphate (ATP) stores after I/R compared to saline-treated counterparts (830.5±108.3 U/L, 56.5±11.0 U/mg protein and 1.93±0.47 μmol/g vs. 505.8± 184.2 U/L, 41.5±10.2 U/mg protein and 3.05±0.55 μmol/g respectively, P<0.01, P<0.05 and P<0.01 respectively). The hepatocyte injury was further exacerbated and the overall survival rate was significantly decreased after I/R in animals given by allopurinol compared to those pretreated by saline (P<0.05). L-NAME and allopurinol co-treated animals exhibited more severe liver injury (P<0.05 and P<0.01) and a further decreased overall survival rate (P<0.05) compared to L-NAME or allopurinol alone-treated counterparts, but they were not different from carboxy-PTIO treated animals (P>0.05). CONCLUSION:NO2--derived NO by XOR in the hypoxic and acidic environment induced by hepatic I/R protects the liver against I/R injury in vivo.Department of General Surgery ( Lu P, Wang CY and Chen DD), and Department of Radiology (Liu F), Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China Cold Spring Harbor Laboratory, New York 11724, USA ( Yao Z) General Surgery Laboratory, Union Hospital, Tongji Medical College , Huazhong University of Science and Technology, Wuhan 430022 , China (Tian Y, Zhang JH and Wu YH) 2005Hepatobiliary & Pancreatic Diseases International2005,4,3:4
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