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Physical Sciences and Mathematics

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1999

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Anneli Lax: In Memoriam, Elena Anne Corie Marchisotto Dec 1999

Anneli Lax: In Memoriam, Elena Anne Corie Marchisotto

Humanistic Mathematics Network Journal

No abstract provided.


Teaching A Humanities Course: A Mathematician’S View, Bill Marion Dec 1999

Teaching A Humanities Course: A Mathematician’S View, Bill Marion

Humanistic Mathematics Network Journal

No abstract provided.


Word Problems, Don Pfaff Dec 1999

Word Problems, Don Pfaff

Humanistic Mathematics Network Journal

No abstract provided.


A Response To Dancis, Margaret Schaffer Dec 1999

A Response To Dancis, Margaret Schaffer

Humanistic Mathematics Network Journal

No abstract provided.


Another Response To Dancis, Ted Eisenberg Dec 1999

Another Response To Dancis, Ted Eisenberg

Humanistic Mathematics Network Journal

No abstract provided.


Evaluation In The Mathematics Classroom, Emam Hoosain, B. Naraine Dec 1999

Evaluation In The Mathematics Classroom, Emam Hoosain, B. Naraine

Humanistic Mathematics Network Journal

No abstract provided.


What Is The Thing Called “Humanistic Mathematics?”, Tamar Apel Dec 1999

What Is The Thing Called “Humanistic Mathematics?”, Tamar Apel

Humanistic Mathematics Network Journal

No abstract provided.


Mathematics Is An Art: The Story Of A One-Time Course, Paul Fjelstad Dec 1999

Mathematics Is An Art: The Story Of A One-Time Course, Paul Fjelstad

Humanistic Mathematics Network Journal

No abstract provided.


A Reflection On The Word: Remembering The Word “Word” Is Reflexive, Paul Fjelstad, Ivan Ginchev Dec 1999

A Reflection On The Word: Remembering The Word “Word” Is Reflexive, Paul Fjelstad, Ivan Ginchev

Humanistic Mathematics Network Journal

No abstract provided.


Calculus For The Liberal Arts: A Humanistic Approach, Kathleen Shannon Dec 1999

Calculus For The Liberal Arts: A Humanistic Approach, Kathleen Shannon

Humanistic Mathematics Network Journal

No abstract provided.


Ode To Mathematics, Sandra Z. Keith Dec 1999

Ode To Mathematics, Sandra Z. Keith

Humanistic Mathematics Network Journal

No abstract provided.


Excerpts From Ivan’S Commandments To Himself, Ivan Niven Dec 1999

Excerpts From Ivan’S Commandments To Himself, Ivan Niven

Humanistic Mathematics Network Journal

No abstract provided.


Divisibility: A Problem Solving Approach Through Generalizing And Specializing, Rina Zazkis Dec 1999

Divisibility: A Problem Solving Approach Through Generalizing And Specializing, Rina Zazkis

Humanistic Mathematics Network Journal

No abstract provided.


The Role Of Values In Mathematics Education, Murad Jurdak Dec 1999

The Role Of Values In Mathematics Education, Murad Jurdak

Humanistic Mathematics Network Journal

No abstract provided.


Book Review: A Tour Of The Calculus By David Berlinski, Bernard Fleishman Dec 1999

Book Review: A Tour Of The Calculus By David Berlinski, Bernard Fleishman

Humanistic Mathematics Network Journal

No abstract provided.


Book Review: Mathematical Reflections By Peter Hilton, Derek Holton And Jean Pedersen, Ladnor Geissinger Dec 1999

Book Review: Mathematical Reflections By Peter Hilton, Derek Holton And Jean Pedersen, Ladnor Geissinger

Humanistic Mathematics Network Journal

No abstract provided.


Roots, Don Pfaff Dec 1999

Roots, Don Pfaff

Humanistic Mathematics Network Journal

No abstract provided.


Tea Tasting And Pascal Triangles, Paul Alper, Yongzhi Yang Dec 1999

Tea Tasting And Pascal Triangles, Paul Alper, Yongzhi Yang

Humanistic Mathematics Network Journal

No abstract provided.


What Else Do We Forget To Tell Our Teachers?: A Response To Dancis, Stephen Sproule Nov 1999

What Else Do We Forget To Tell Our Teachers?: A Response To Dancis, Stephen Sproule

Humanistic Mathematics Network Journal

No abstract provided.


The Studies Of The (Photo) Electrochemical Character On The Electrodeposited Silver Indium Selenium Thin Films, Shaoai Xie Nov 1999

The Studies Of The (Photo) Electrochemical Character On The Electrodeposited Silver Indium Selenium Thin Films, Shaoai Xie

Journal of Electrochemistry

A photoelectrochemical cell(PEC) is constructed,using an AgInSe 2 film photoanode made from electrodeposition and a platinium electrode in aqueous polyiodide or polysufide electrolyte. The V oc and I sc of PEC have been tested and measured, and the effect of chemical decoration on the photoanodes also studied.


Prparation Of Nanocrystaline Tio_2(Anatase)With High Thermal And Textural Sability By Electrochemical Method, Daobao Chu, Xingfu Zhou Nov 1999

Prparation Of Nanocrystaline Tio_2(Anatase)With High Thermal And Textural Sability By Electrochemical Method, Daobao Chu, Xingfu Zhou

Journal of Electrochemistry

Titanium alkoxides were prepared by anodic dissolution of metallic titanium in absolute ethanol in the presence of HN(C 2H 5) 2·HCl (electro_conductive additives).The solution was directly hydrolyzed to prepare nanocrystalline of TiO 2 (about 10nm)by a sol_gel process.The precursor gels was calcined at T =450 ℃ and 720 ℃for 30 min,and nanocrystalline of TiO 2 (anatase) with high textural and thermal stability was obtained.FTIR,XRD,TEM,were used to characterize the structure of titanium alkoxides and nanocrystalline of TiO 2.The characteristics of nanocrystalline of TiO 2 was depended on the properties of titanium alkoxides.The Ti(OEt) 4 as a source of titanium yielded the …


Characterization And Electrochemical Behaviour Of Ce(Ⅲ) Amino Acid Imidazole Ternary Complexes, Huixia Wu, Zemin Wang, Haifeng Yang, Zongrang Zhang Nov 1999

Characterization And Electrochemical Behaviour Of Ce(Ⅲ) Amino Acid Imidazole Ternary Complexes, Huixia Wu, Zemin Wang, Haifeng Yang, Zongrang Zhang

Journal of Electrochemistry

Two Ce(Ⅲ)_amino acid_imidazole teranry complexe were synthesized,These complexes have the composition of Ce(Trp) 3IM(NO 3) 3·3H 2O and Ce(Phe) 3IM(NO 3) 3 respectively. The IR spectra indicate that the carboxy group of amino_acid and the N atoms of imidazole are coordinated with Ce(Ⅲ) ion.Cyclic voltammetry was used to study the electrochemical behaviour of Ce(Ⅲ) ion,the mixture of Ce(Ⅲ) with ligands,and Ce(Ⅲ) binary or ternary complexes. Within the scan range of -0.1 to 1.10 V (vs.SCE),both of ternary complexes depicted completely irreversible electron transfer process.


Studies On Methods Of Fuel Cells Electrodes Preparation, Jun Gu, Sheng Sui, Guangqiang Li, Zhitong Sui Nov 1999

Studies On Methods Of Fuel Cells Electrodes Preparation, Jun Gu, Sheng Sui, Guangqiang Li, Zhitong Sui

Journal of Electrochemistry

In fuel cells,the structure of electrodes is an important factor which effect the cell performance.To improve the structure and the performance of electrodes,a new method of providing fuel cell electrodes is proposed in this paper.PTFE(polytetrafluoroethylene) and ethyne black was ground for about half an hour in a high_speed grinder,then the catalyst was added into the grinder and milled for an hour.This milled catalyst was transferred into a mixer followed by the addition of surface_active agent. After a suspension was formed,it was filtered under vacuum condition.Then a thin uniform filter_cake of the catalyst was formed,which was rolled together with a current_collecting …


The Electrochemical Behaviors Of Superoxide Dismutase At Promoter Modified Gold Electrode, Xiaqin Wu, Xiaoyun Meng, Zhesu Wang, Zongrang Zhang Nov 1999

The Electrochemical Behaviors Of Superoxide Dismutase At Promoter Modified Gold Electrode, Xiaqin Wu, Xiaoyun Meng, Zhesu Wang, Zongrang Zhang

Journal of Electrochemistry

The electron_transfer process of superoxide dismutase was investigated by cyclic voltammetry at the 4,4'_dithiodipyridine,L_cysteine,histidine and arginine modified gold wire electrodes repectively.The quasi_reversible behavior was observed at L_cysteine modified gold electrode.An irreversible electrochemical behavior has been observed at hisdinine modified gold wire electrode.


Aes Multi_Layer Structural Analysis Of Si Based Anodic Porous Alumina Films And Studies On Its Formation Mechanism, Junhui Wu, Jianping Zou, Qing Zhu, Ximao Bao Nov 1999

Aes Multi_Layer Structural Analysis Of Si Based Anodic Porous Alumina Films And Studies On Its Formation Mechanism, Junhui Wu, Jianping Zou, Qing Zhu, Ximao Bao

Journal of Electrochemistry

nm aluminum films were deposited onto a p_type,0.5 Ω·cm, 〈100〉 oriented silicon wafers using electron beam evaporation technique.Then,the wafers was immersed in 15 wt% H 2SO 4 for porous_type over_anodization under a constant voltage of DC 60V.During the anodization,the temperature of the electrolyte was maintained at 0 ℃.The obtained samples were investigated by means of transmission electron microscopy,scanning electron microscopy,and AES depth profile for multi_layer structural information.In addition, the basic anodic formation mechanism of the Si_based aluminum films was brielfly discussed.


A Novel Reaction Region Moving Electrode System For Electrochemical Power Sources, Jinkua You, Que Tu, Zhengjian Wang, Jie Sun, Zugeng Lin Nov 1999

A Novel Reaction Region Moving Electrode System For Electrochemical Power Sources, Jinkua You, Que Tu, Zhengjian Wang, Jie Sun, Zugeng Lin

Journal of Electrochemistry

In most of practical rechargeable batteries, charging/discharging process is always concerned with phase_transformation in the solid state. Due to the irreversibility of the phase_transformation, the cyclic performance of the rechargeable batteries are limited. In this paper, a novel reaction_region moving counter electrode system is constructed in our laboratory. The electrode system is operated at room temperature and cycled in solid_liquid phase during charging/discharging processes. With this electrode, the metal_complexes are firstly deposited(i.e. charging process) on the nearest working electrode and gradually extended to those another working electrodes several centimeters away from the counter electrode. The deposite is dissolved again into …


Study On Electrochemical Reduction Properties Of Nitrobenzene, Chuna Ma, Wenkui Zhang, Hui Huang, Yongping Gan Nov 1999

Study On Electrochemical Reduction Properties Of Nitrobenzene, Chuna Ma, Wenkui Zhang, Hui Huang, Yongping Gan

Journal of Electrochemistry

The electrochemical reduction characteristics of nitrobenzene was extensively investigated by using the techniques such as quasi_steady_state polarization,cyclic voltammetry,fast linear potential sweep method and chronoamperometry in this paper.The electroanalytic properties of Cu,Cu_Hg and Cu_Ni electrodes were evaluated.Based on the study of the transient steping behaviour of nitrobenzene to PAP,the reduction mechanism was discussed.The results showed that the transition steps existed on the electrochemical reduction of nitrobenzene in acidic solution,the reactant is also absorbed on electrodes surface. The control step in the reduction of nitrobenzene was ascribed to the diffusion of nitrobenzene and its electrochemical reductive products in the acid solution.


High Performance Proton Exchange Membrane Fuel Cells, Jingrong Yu, Baolian Yi, Ming Han, Xiaoliang Cheng, Zhigang Shao, Jingxin Zhang Nov 1999

High Performance Proton Exchange Membrane Fuel Cells, Jingrong Yu, Baolian Yi, Ming Han, Xiaoliang Cheng, Zhigang Shao, Jingxin Zhang

Journal of Electrochemistry

Proton_exchange membrane fuel cells(PEMFC) using a perfluorosulfonic acid proton exchange membrane as an electrolyte can simplify water and electrolyte management.In this paper,the effects of thickness of PEM on the performance of PEMFC were studied.The Nafion_112 PEM and low platinum loading E_TEK electrode yielded very high power density,of the order of 0.95 W/cm 2.The energy_conversion efficiency,the degree of platinum utilization and stability for PEMFC using Nafion 112 and E_TEK electrode were also investigated.


Photoelectrochemical Studies On The Tio_2 Nanostructured Porous Film Sensitized By Cyanine Dye, Li Zhang, Maizhi Yang, Xuebin Qiao, Yanzhong Hao, Enqing Gao, Shengmin Cai Nov 1999

Photoelectrochemical Studies On The Tio_2 Nanostructured Porous Film Sensitized By Cyanine Dye, Li Zhang, Maizhi Yang, Xuebin Qiao, Yanzhong Hao, Enqing Gao, Shengmin Cai

Journal of Electrochemistry

The photoelectrochemical behaviors of the TiO 2 nanostructured porous film sensitized by cyanine dye were investigated in this paper.The results showed that the excitaed state level matched the conduction band edge of TiO 2 nanoparticle.Therefore the sensitization of the dye can increase the photocurrent intensity of the TiO 2 nanostructured electrode obviously and results in a red-shift of optical absorption from the ultra_violet region to the visible.As a result,the light_to _electricity conversion efficiency was improved evidently,the maximum value of IPCE has reached 12.1%.


Surface Enhanced Raman Spectroscopic Study Of Scn - Adsorbed At The Copper And Gold Nanowire Arrays, Jianlin A Yao, Guoping Pan, Kuanhong Xue, Yong Xie, Jing Tang, Bin Ren, Dongmei Sun, Bingwei Mao, Zhongqun Tian Nov 1999

Surface Enhanced Raman Spectroscopic Study Of Scn - Adsorbed At The Copper And Gold Nanowire Arrays, Jianlin A Yao, Guoping Pan, Kuanhong Xue, Yong Xie, Jing Tang, Bin Ren, Dongmei Sun, Bingwei Mao, Zhongqun Tian

Journal of Electrochemistry

Two_dimensional arrays of Cu and Au nanowires have been fabricated by template synthesis method, using the anodic aluminum oxidation films as the template. The morphology of the nanowire array was monitored by atomic force microscope (AFM) in the dissolution processes of the alumina film. Based on the probe molecule strategy, the spectral feature of SCN - adsorbed at the Cu and Au nanowires with different diameters has been investigated by surface enhanced Raman spectroscopy (SERS). The results reveal that the intensity of the SERS bands depends on the length of the exposed nanowires. The C≡N stretching vibration frequency (ν CN …