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Articles 1 - 30 of 563
Full-Text Articles in Physical Sciences and Mathematics
News From Cart, Michael A. Krol, Julia Stakhnevich
News From Cart, Michael A. Krol, Julia Stakhnevich
Bridgewater Review
No abstract provided.
Introduction To Special Issue On Radiation Effects, P. Andrew Karam
Introduction To Special Issue On Radiation Effects, P. Andrew Karam
The University of New Hampshire Law Review
[Excerpt] "How dangerous is radiation? How much radiation does it take to give us cancer? Are we wasting money on overly restrictive regulations, or are we not being sufficiently protective of our radiation workers and the public? How much clean-up is necessary on our Department of Energy facilities? What about Yucca Mountain and nuclear reactor plants – can they be made safe?
These are only a few of the questions that have been asked, and will continue to be asked, about radiation. Unfortunately, these all come down, in part or in whole, to the question “What is the shape of …
Historical Development Of The Linear Nonthreshold Dose-Response Model As Applied To Radiation, Ronald L. Kathren
Historical Development Of The Linear Nonthreshold Dose-Response Model As Applied To Radiation, Ronald L. Kathren
The University of New Hampshire Law Review
[Excerpt] "Despite the nearly universal adoption of the linear nonthreshold dose response model (LNT) as the primary basis for radiation protection standards for the past half century, the LNT remains highly controversial and a contentious topic of discussion among health physicists, radiation biologists, and other radiological scientists. Indeed, it has been pointed out that the LNT has assumed the status of a paradigm, synonymous with an ideal, standard, or paragon or perhaps to some, a sacred cow. Reduced to its very basics, the LNT postulates that every increment of ionizing radiation dose, however small, carries with it a commensurate increase …
Review Of "The Health Of Nations: Infectious Disease, Environmental Change, And Their Effects On National Security And Development," By Andrew T. Price-Smith, Andrew Mierins
The University of New Hampshire Law Review
[Excerpt] "Andrew T. Price-Smith, author of The Health of Nations: Infectious Disease, Environmental Change, and Their Effects on National Security and Development, provides a well documented and reasoned analysis of the need for world leaders, including the United States, to place the threat of infectious disease on the front burner of consideration when shaping both national and international policy. Professor Price-Smith has provided both empirical data and historical analysis to support the impassioned plea for this natural threat to be taken seriously. The book is geared toward the academic community and policy analysts; however, other professionals not involved in these …
The Debate On The Health Effects Attributable To Low Radiation Exposure, Abel J. Gonzalez
The Debate On The Health Effects Attributable To Low Radiation Exposure, Abel J. Gonzalez
The University of New Hampshire Law Review
[Excerpt] "Few scientific issues have aroused passions more than the dispute about the health effects attributable to low levels of exposure to ionizing radiation (or radiation in short) and the currently authoritative dose response hypothesis, termed “linear non-threshold,” or LNT. Finding out whether health effects are induced by low-level radiation exposures, and if so, what they are, has become a kind of contest rather than a serious scientific inquiry. Sometimes it seems that rationality, or a methodical examination of the unknown, has disappeared from this debate. While the confrontation of different hypotheses is typical in academic discussions – at least …
Review Of "The Future Of Life," By Edward O. Wilson, Bryan Erickson
Review Of "The Future Of Life," By Edward O. Wilson, Bryan Erickson
The University of New Hampshire Law Review
[Excerpt] "It is refreshing to read an environmental diatribe where the writer has both the authority of a world expert and a willingness to compromise to pursue realistic solutions. Wilson is a Harvard biology professor, two-time Pulitzer Prize winner, and a director of the Nature Conservancy. In The Future of Life, he presents a succinct evaluation of the great ecological issues of our day, focusing on the rapid pace of species extinctions, and on the promise of finding a balance between conservation and human activity that will bring the extinctions to a halt."
Effects Of The Shape Of The Radiation Dose-Response Curve On Public Acceptance Of Radiation And Nuclear Energy, Audeen W. Fentiman
Effects Of The Shape Of The Radiation Dose-Response Curve On Public Acceptance Of Radiation And Nuclear Energy, Audeen W. Fentiman
The University of New Hampshire Law Review
[Excerpt] “The public generally accepts the premise that exposure to radiation can have an undesirable effect. Furthermore, it believes that as the radiation dose increases, the magnitude of the effect will increase. On the other hand, while the background radiation dose varies from a few hundred millirem/year (a few millisieverts/yr) in some places to a few thousand millirem/yr (tens of millisieverts/yr) in others, researchers have been unable to find a correlation between the level of background radiation and incidence of cancer or other maladies attributable to radiation.
…
Because there is considerable controversy about the relationship between radiation dose and …
The U.S. And Mexico Sin Fronteras - Without Borders: Sustainable Development From A Local Perspective, Paulette Stenzel
The U.S. And Mexico Sin Fronteras - Without Borders: Sustainable Development From A Local Perspective, Paulette Stenzel
William & Mary Environmental Law and Policy Review
No abstract provided.
Preparation And Electrochemical Lithium Intercalation Performance Of Different Shaped Carbon Nanotube, Mao-Hui Chen, Zhen-Cai Huang, Guo-Tao Wu, Jin-Kua You, Zu-Geng Lin
Preparation And Electrochemical Lithium Intercalation Performance Of Different Shaped Carbon Nanotube, Mao-Hui Chen, Zhen-Cai Huang, Guo-Tao Wu, Jin-Kua You, Zu-Geng Lin
Journal of Electrochemistry
In the present work, different shaped carbon nanotubes were produced by the general CVD and the template method at different temperature (600 ℃,700 ℃) with the reaction gas of acetylene. The morphology, structure and the electrochemical lithium intercalation performance were comparatively studied and characterized by TEM, HRTEM, SEM, XRD, Raman techniques and Charge/Discharge Test. It was found that the different preparation methods and temperatures all had an obvious effect on these properties of carbon nanotubes. In our samples, with the increase of preparation temperature, the degree of crystallinity decreased, and the reversible specific capacity increased respectively.
Mechanistic Study Of Oxidation Of Hypophosphite On Pt Electrodes By Sniftirs, Tai-Xiang Jiang, Hui-Huang Wu
Mechanistic Study Of Oxidation Of Hypophosphite On Pt Electrodes By Sniftirs, Tai-Xiang Jiang, Hui-Huang Wu
Journal of Electrochemistry
The oxidation of hypophosphite on a polycrystalline platinum electrode was studied by SNIFTIRS and cyclic voltammetry, the in-situ IR spectra were analyzed as a function of Pt electrode potentials in the solution of 0.5 mol/L H 2SO 4+0.1 mol/L NaH 2PO 2. It was found that the dissociative adsorption of hypophosphite ions occurs on Pt surface, and the oxidation product is H 3PO 4, rather than H 2PO 3 - which was considered to produce on Ni electrodes, thereby a new insight into mechanism of hypophosphite oxidation on Pt in acidic media was provided.
Nano-Sized Cobalt-Based Oxides As Negative Electrode For Lithium-Ion Batteries, Feng Huang, Zheng-Yong Yuan, Yun-Hong Zhou, Ju-Tang Sun
Nano-Sized Cobalt-Based Oxides As Negative Electrode For Lithium-Ion Batteries, Feng Huang, Zheng-Yong Yuan, Yun-Hong Zhou, Ju-Tang Sun
Journal of Electrochemistry
Nanosized cobalt-based oxide (Co 3O 4, CoB 1.36 O 2.8 and CoB 0.5 Al 0.1 O 1.5 ) samples were prepared by rheological phase method and were tested as anodes in secondary lithium batteries. The cells were cycled between 0.01V and 3.00 V. The best electrochemical performance was obtained from the Li/Co 3O 4 cell, which retained 95% of its initial capacity (931 mAh/g) after 30 cycles. The doping of B, Al reduced the reversible capacity during the first discharge/charge cycle, and the quantity of reversible capacity reduced with B, A1 increasing. The modifying structures at difference charge and discharge …
Electrochemical Preparation And Reaction Mechanism Of Nanocrystalline Nio, Jia-Shan Gu, Ai-Jie Han, Xing-Fu Zhou, Dao-Bao Chu, Chang-Jian Lin
Electrochemical Preparation And Reaction Mechanism Of Nanocrystalline Nio, Jia-Shan Gu, Ai-Jie Han, Xing-Fu Zhou, Dao-Bao Chu, Chang-Jian Lin
Journal of Electrochemistry
Metallic nickel was electrochemically dissolved in absolute ethanol and acetylacetone mixed solutions and in the presence of Bu 4NBr (as an electron-conductive additive). The electrolyte solution containing the precursor was then directly hydrolyzed to obtain nanocrystalline NiO. The precursor was characterized by FTIR?HNMR?Raman spectra and the nano-powder was characterized by XRD and TEM. The results showed that the NiO powder after calcined at 450 ℃ had formed the cubic NaCl structure and the nanocrystalline NiO prepared by this method had narrow size distribution of 10~15 nm. Moreover, the product yield could be improved by controlling temperature below 30~40 ℃. The …
Electrocatalytic Oxidation Of Formic Acid On Molybdate-Modified Platinum Electrode, Jun-Hua Du, Xue-Hui Xu, Hong Li, Hong-Yu Cheng, Wei-Shan Li
Electrocatalytic Oxidation Of Formic Acid On Molybdate-Modified Platinum Electrode, Jun-Hua Du, Xue-Hui Xu, Hong Li, Hong-Yu Cheng, Wei-Shan Li
Journal of Electrochemistry
The electrochemical behavior of molybdates on a platinum electrode in H 2SO 4 solutions with different H 2SO 4 concentrations was studied by cyclic voltammetry and double chronoamperometry. Molybdates were reduced to adsorb hydrogen molybdenum bronzes on the platinum electrode in H 2SO 4 solutions during cathodically potential sweep. The hydrogen molybdenum bronzes were oxidized to different forms of hydrogen molybdenum bronzes with less hydrogen, depending on the H 2SO 4 concentration. Platinum electrode was modified by these hydrogen molybdenum bronzes. However, this modified electrode was not stable in H 2SO 4 solutions. The modified electrode was used to study …
Preparation And Performance Of Lifeo_2 Coated Nickel Oxide Cathode For Molten Carbonate Fuel Cells, Chun-Ming Wang, Fei Li, Ke-Ao Hu
Preparation And Performance Of Lifeo_2 Coated Nickel Oxide Cathode For Molten Carbonate Fuel Cells, Chun-Ming Wang, Fei Li, Ke-Ao Hu
Journal of Electrochemistry
A novel cathode for molten carbonate fuel cells was prepared by coating LiFeO 2 over the surface of porous NiO cathode by a simple combustion process. The analytical results of X-ray diffraction (XRD), energy dispersive analysis of X-ray (EDAX), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) indicated that the LiFeO 2 coating on the surface of NiO particles consisted of nonometer-sized LiFeO 2 grains and sintered tightly with the NiO particles. The LiFeO 2 coating dramatically reduced the contacting area of NiO with the carbonate melts, thus the solubility of NiO in the carbonate melts was decreased. Meanwhile, …
Steady State Simulation Of Ysz Intermediate-Temperature Fuel Cell, Zi-Jing Lin, Ye Gu, Xiao-Hua Zhang
Steady State Simulation Of Ysz Intermediate-Temperature Fuel Cell, Zi-Jing Lin, Ye Gu, Xiao-Hua Zhang
Journal of Electrochemistry
With a coupled 2D electrochemical and thermal modeling software, the characteristics of the steady state operation of the intermediate-temperature fuel cell with thin yttria-stabilized zirconia(YSZ) electrolyte was analyzed. The parameters of I-V equation were obtained from fitting the experiment results and the choice of grid points was determined by balancing the accuracy requirement and computational efficiency. The temperature fields at different operation circumstances such as flow designs, material choices for interconnect, were examined. The dependences of the output power and cell efficiency on the operating voltage at different temperatures were studied. Based upon the analysis of the temperature profile, it …
Effect Of Dissolved Oxygen On The Corrosion Behavior Of Coalesced Copper And Stainless Steel-206 In Acetic Solutions, Rong-Zong Hu, Xiong-Cao Zhao, Yu-Hua Weng, Chang-Jian Lin
Effect Of Dissolved Oxygen On The Corrosion Behavior Of Coalesced Copper And Stainless Steel-206 In Acetic Solutions, Rong-Zong Hu, Xiong-Cao Zhao, Yu-Hua Weng, Chang-Jian Lin
Journal of Electrochemistry
Linear sweeping technique and dissolving oxygen sensor were used to study the effect of dissolved oxygen and relating factors on the corrosion behavior of coalesced copper and stainless steel-206 in acetic solutions. It was found: 1. The existing of dissolved oxygen is one of the important factors, which strongly influenced the corrosion behavior of coalesced copper and stainless steel-206 in acetic solution. 2. The existing of dissolved oxygen is benefitial to the preventing stainless steel-206 from corrosion in acetic solutions, but damage to the preventing coalesced copper from corrosion. 3. At the high temperature since the dissolved oxygen was escaping …
Improvement Of The Low Temperature Electrochemical Performance Of Ab_5-Type Hydrogen Storage Alloy, Hui Ye, Zhu Wu, Zhi-Lin Li, Hong Zhang
Improvement Of The Low Temperature Electrochemical Performance Of Ab_5-Type Hydrogen Storage Alloy, Hui Ye, Zhu Wu, Zhi-Lin Li, Hong Zhang
Journal of Electrochemistry
Optimizing the rare earth composition and doping with boron have been used to improve the low temperature performance of AB 5 hydrogen storage alloy.The results show that Ce-rich alloy with a proper amount of boron is suitable for Ni/MH battery with the lower-limit temperature down to 238 K under smaller current density (120 mA/g). The improvement of low temperature performance of hydrogen storage alloy is well consistent with its microstructure,thermodynamic and kinetic properties.
Review Of Mathematical Model For Proton Exchange Membrane Fuel Cell, Shan-Hai Ge, Bao-Lian Yi, Hua-Min Zhang
Review Of Mathematical Model For Proton Exchange Membrane Fuel Cell, Shan-Hai Ge, Bao-Lian Yi, Hua-Min Zhang
Journal of Electrochemistry
In the review with 49 references, the mathematical models for proton exchange membrane fuel cell (PEMFC) were summarized. The mechanistic model and empirical model were introduced. Transfer in the membrane, catalyst layer,diffusion layer and flow field of PEMFC were described. The importance of water and heat management was analyzed. The dimension, complexity and solving methods of the PEMFC model were discussed. The importance and validity to develop a model with time dimension are put forward.
Manufacture Of 1 Kw Molten Carbonate Fuel Cell Stack, Sheng Sui, Xin-Jian Zhu, Zheng-Yu Fan, Cao Guang-Yi And
Manufacture Of 1 Kw Molten Carbonate Fuel Cell Stack, Sheng Sui, Xin-Jian Zhu, Zheng-Yu Fan, Cao Guang-Yi And
Journal of Electrochemistry
A molten carbonate fuel cell stack with an active area of 240 mm×140 mm consisted of 30 cells.The gas feed system works via interior manifolds,and the stack placed in a couple of self-chest,coupled with a heater at the bottom and other fours surrounded,to keep uniformity of temperature.Under ambient pressure and 650 ℃,fed with hydrogen and air as anode and cathode gases respectively,the stack gave a current density of 150 mA/cm 2 at an average cell voltage of 0.7 V.The peak output of the stack was 1.06 kW during its performance of 300 h.
Lithium Intercalation Performance Of P-Doped Phenolic Resin Pyrolysis Carbon, Bao-Hua Li, Kai-Xi Li, Yonggen Lv, Chun-Xiang Lv, Dong Wu, Li-Cheng Ling
Lithium Intercalation Performance Of P-Doped Phenolic Resin Pyrolysis Carbon, Bao-Hua Li, Kai-Xi Li, Yonggen Lv, Chun-Xiang Lv, Dong Wu, Li-Cheng Ling
Journal of Electrochemistry
Phosphorus-doped phenolic resin carbon was prepared by low temperature(700 ℃)pyrolysis of thermoplastic phenolic resin containing different amounts of phosphorus pentoxide after curing. X-ray diffraction pattern and the constang-current charge-discharge properties of phenolic resin carbon were studied. The results showed that the phenolic resin carbon microstructure became out of order with increasing of content phosphorus pentoxide,otherwise,the first discharge reversible capacities increased firstly and then decreased. The first discharge reversible capacity of phenolic resin carbon containing 9wt% phosphorus pentoxide was 528 mA·h·g -1 which was higher than that of non-phosphorus doped phenolic resin carbon(230 mA·h·g -1 ) did.
Studies On The Inhibition Of Yki-05 Corrosion Inhibitor To 907a Steel In Different Immersed Environments, Hui Yu, Jian-Hua Wu, Hong-Ren Wang, Jian-Hua Qian, Guang-Zhang Chen
Studies On The Inhibition Of Yki-05 Corrosion Inhibitor To 907a Steel In Different Immersed Environments, Hui Yu, Jian-Hua Wu, Hong-Ren Wang, Jian-Hua Qian, Guang-Zhang Chen
Journal of Electrochemistry
The inhibition of YKI-05 Corrosion inhibitor in different conditions was studied using potentiodynamic polarization technique. The resuled shown that (i) the inhibitor film layer was formed stably on the surface of 907A steel electrode when it was persistently immersed in static seawater and the inhibition efficiency reached 90% or so. The inhibition mechanism is negative catalytic effect. (ii)the inhibitior film layer was not stable when the electrode was periodically immersed in seawater and was destroyed more significantly with the increase of electrode exposing time. The film was only a covered layer on the surface of electrode and it retarded both …
Detection And Analysis Of Sec1 Immunological Reaction By Afm And Electrochemical Method, Sa-Ying Dong, Hong-Ren Wang
Detection And Analysis Of Sec1 Immunological Reaction By Afm And Electrochemical Method, Sa-Ying Dong, Hong-Ren Wang
Journal of Electrochemistry
The goals of this work were to demonstrate the ability of atomic force microscopy (AFM) to detect various immunological processes between antibodies and antigens.A sensor was designed by covalently linking the antibody of staphylococcal enterotoxin Cl (SEC1) on the self-assembled gold surface. This sensor permitted detection of antibody-antigen recognition events which were highly correlated with the topography under different conditions. The statistic data of AFM were analysed. As control experiments, nonspecific antigens and lower concentration SEC1 antigens were directly observed. In addition, an acidic solution was used to break the antigen-antibody pair and made the sensor reuse. Electrochemical evidence was …
An Investigation On Microstructure And Performance Of The Recasting Perfluorosulfonated Membrane, Feng-Ling Liu, Rong Zeng, Pei-Jin Li, Pin-Qing Wang, Chang-Hong Zhao
An Investigation On Microstructure And Performance Of The Recasting Perfluorosulfonated Membrane, Feng-Ling Liu, Rong Zeng, Pei-Jin Li, Pin-Qing Wang, Chang-Hong Zhao
Journal of Electrochemistry
The microsturcture and performance of the recasting perfluorosulfonated membrane were investigated by comparison with Nafion . The results indicated that although chemical components of the recasting membrane FYM1150 kept the same as Nafion , the dry FYM1150 differed from dry Nafion membrane in structure, the former possessed some small pores which are not through-holes having a diameter of 50~300 nm while the latter had almost no pores; The mechanical properties of the FYM1150 were better than those of Nafion ; The discharge performance at high current density of MEA using FYM1150 membrane as an electrolyte was also better than …
Properties Of Domestic Natural Graphite Used For Li-Ion Batteries, Cui-Wei Du, Yu-Juan Zhao, Gang Zhang, Yin-Shun Wu, Qing-Guo Liu
Properties Of Domestic Natural Graphite Used For Li-Ion Batteries, Cui-Wei Du, Yu-Juan Zhao, Gang Zhang, Yin-Shun Wu, Qing-Guo Liu
Journal of Electrochemistry
The structure, physical characteristics and electrochemical properties of the natural graphite produced in Shandong province have been studied. The result of X-ray diffraction showed that the graphite consisted of hexagonal structure and rhombic structure (30% rhombic structure). It was fine crystal graphite. Used as a negative material of Lithium ion battery, the natural graphite showed excellent voltage and high energy capacity, but poor compatibility with electrolyte solution containing propylene carbonate (PC) for its own structure limitation.
Jmasm4: Critical Values For Four Nonparametric And/Or Distribution-Free Tests Of Location For Two Independent Samples, Bruce R. Fay
Jmasm4: Critical Values For Four Nonparametric And/Or Distribution-Free Tests Of Location For Two Independent Samples, Bruce R. Fay
Journal of Modern Applied Statistical Methods
Researchers engaged in computer-intensive studies may need exact critical values, especially for sample sizes and alpha levels not normally found in published tables, as well as the ability to control ‘best-fit’ criteria. They may also benefit from the ability to directly generate these values rather than having to create lookup tables. Fortran 90 programs generate ‘best-conservative’ (bc) and ‘best-fit’ (bf) critical values with associated probabilities for the Kolmogorov-Smirnov test of general differences (bc), Rosenbaum’s test of location (bc), Tukey’s quick test (bc and bf)) and the Wilcoxon rank-sum test (bc).
Constructive Criticism, Ronald C. Serlin
Constructive Criticism, Ronald C. Serlin
Journal of Modern Applied Statistical Methods
Attempts to attain knowledge as certified true belief have failed to circumvent Hume’s injunction against induction. Theories must be viewed as unprovable, improbable, and undisprovable. The empirical basis is fallible, and yet the method of conjectures and refutations is untouched by Hume’s insights. The implications for statistical methodology is that the requisite severity of testing is achieved through the use of robust procedures, whose assumptions have not been shown to be substantially violated, to test predesignated range null hypotheses. Nonparametric range null hypothesis tests need to be developed to examine whether or not effect sizes or measures of association, as …
Extensions Of The Concept Of Exchangeability And Their Applications, Phillip I. Good
Extensions Of The Concept Of Exchangeability And Their Applications, Phillip I. Good
Journal of Modern Applied Statistical Methods
Permutation tests provide exact p-values in a wide variety of practical testing situations. But permutation tests rely on the assumption of exchangeability, that is, under the hypothesis, the joint distribution of the observations is invariant under permutations of the subscripts. Observations are exchangeable if they are independent, identically distributed (i.i.d.), or if they are jointly normal with identical covariances. The range of applications of these exact, powerful, distribution-free tests can be enlarged through exchangeability- preserving transforms, asymptotic exchangeability, partial exchangeability, and weak exchangeability. Original exact tests for comparing the slopes of two regression lines and for the analysis of …
Within Groups Multiple Comparisons Based On Robust Measures Of Location, Rand R. Wilcox, H. J. Keselman
Within Groups Multiple Comparisons Based On Robust Measures Of Location, Rand R. Wilcox, H. J. Keselman
Journal of Modern Applied Statistical Methods
Consider the problem of performing all pair-wise comparisons among J dependent groups based on measures of location associated with the marginal distributions. It is well known that the standard error of the sample mean can be large relative to other estimators when outliers are common. Two general strategies for addressing this problem are to trim a fixed proportion of observations or empirically check for outliers and remove (or down-weight) any that are found. However, simply applying conventional methods for means to the data that remain results in using the wrong standard error. Methods that address this problem have been proposed, …
A Comparison Of The D’Agostino S_U Test To The Triples Test For Testing Of Symmetry Versus Asymmetry As A Preliminary Test To Testing The Equality Of Means, Kimberly T. Perry, Michael R. Stoline
A Comparison Of The D’Agostino S_U Test To The Triples Test For Testing Of Symmetry Versus Asymmetry As A Preliminary Test To Testing The Equality Of Means, Kimberly T. Perry, Michael R. Stoline
Journal of Modern Applied Statistical Methods
This paper evaluates the D’Agostino SU test and the Triples test for testing symmetry versus asymmetry. These procedures are evaluated as preliminary tests in the selection of the most appropriate procedure for testing the equality of means with two independent samples under a variety of symmetric and asymmetric sampling situations. Key words: symmetry; asymmetry; preliminary testing.
Adaptive Tests For Ordered Categorical Data, Vance W. Berger, Anastasia Ivanova
Adaptive Tests For Ordered Categorical Data, Vance W. Berger, Anastasia Ivanova
Journal of Modern Applied Statistical Methods
Consider testing for independence against stochastic order in an ordered 2xJ contingency table, under product multinomial sampling. In applications one may wish to exploit prior information concerning the direction of the treatment effect, yet ultimately end up with a testing procedure with good frequentist properties. As such, a reasonable objective may be to simultaneously maximize power at a specified alternative and ensure reasonable power for all other alternatives of interest. For this objective, none of the available testing approaches are completely satisfactory. A new class of admissible adaptive tests is derived. Each test in this class strictly preserves the Type …