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2001

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Full-Text Articles in Physical Sciences and Mathematics

The Role Of Environmental Analogs In Identifying Potentially Invasive Woody Plants In Iowa, Mark P. Widrlechner Dec 2001

The Role Of Environmental Analogs In Identifying Potentially Invasive Woody Plants In Iowa, Mark P. Widrlechner

Journal of the Iowa Academy of Science: JIAS

Americans cultivate a large and diverse range of introduced woody plants as important sources of food and forest products, as well as for urban horticulture, amenity and wildlife plantings, and windbreaks. A small number of these species have become serious pests, disrupting well-established native plant communities or functioning as range and agricultural weeds. More of these species are not serious pests today, but have escaped cultivation and serve as potential sources of future outbreaks. Two other sources of potentially invasive woody plants are found among species that are not or are only rarely cultivated, about which we often know little …


Front Matter Dec 2001

Front Matter

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Invasive Species In Iowa: An Introduction, James J. Dinsmore, Neil P. Bernstein Dec 2001

Invasive Species In Iowa: An Introduction, James J. Dinsmore, Neil P. Bernstein

Journal of the Iowa Academy of Science: JIAS

Concern over the increasing spread of invasive species and the potential impacts of those species on native communities has been the subject of several books and hundreds of research papers in recent years. President Clinton's Executive Order on invasive species in February1999 raised national attention to this issue. Natural resource agencies have been plagued by an ever-increasing number of invasive species and now consider this issue the second most important problem (after habitat loss) in their fight to maintain some semblance of natural communities on this planet. One group of experts estimated that in the United States alone, invasives cost …


War On Weeds: Winning It For Natural Areas, Jerry E. Asher Dec 2001

War On Weeds: Winning It For Natural Areas, Jerry E. Asher

Journal of the Iowa Academy of Science: JIAS

I am delighted to be here with you today to discuss the rapidly accelerating damage that invasive exotic plants are inflicting on natural areas in this country. This problem may seem overwhelming, but you need not despair because there are economical, realistic, and effective strategies available to meet this challenge.

There are two purposes to this presentation: to give you information you can use to convince others that invasive exotic plants are seriously harmful, and to suggest that we can win this war on invasive exotic plants if we engage enough of the right people.


An Overview And Management Plan Of Iowa's Non-Native, Invasive, Terrestrial Forbs, Deborah Q. Lewis, Richard O. Pope Dec 2001

An Overview And Management Plan Of Iowa's Non-Native, Invasive, Terrestrial Forbs, Deborah Q. Lewis, Richard O. Pope

Journal of the Iowa Academy of Science: JIAS

Non-native, invasive forb species have been a problem in Iowa since the earliest decades of Iowa's European settlement. The history of studies of Iowa's invasive plants began with L. H. Pammel, and these studies continue to present. Three tables cite the occurrence of many of these species in the state, with Table 1 listing 93 non-native forbs reported by Pammel, Table 2 citing ten invasive forbs of natural areas, and Table 3 adding 38 observed or potential aggressive species of Iowa's anthropogenic and natural areas.

There has been a divergence of interest and research in the management of invasive species …


Iowa's Non-Native Graminoids, Thomas R. Rosburg Dec 2001

Iowa's Non-Native Graminoids, Thomas R. Rosburg

Journal of the Iowa Academy of Science: JIAS

Iowa's non-native graminoids include 60 species of grasses and one species of bulrush. The exotic grass species comprise a large proportion (about 31%) of the total species richness of grasses in Iowa, which are second only to the Asteraceae in terms of total species. About half of the non-native graminoids (52%) occur sporadically and form sparse, non-invasive populations, while eighteen species (about 30%) are commonly encountered in large populations throughout the state. About 60% are annuals and a large majority (89%) has been introduced from either Europe or Asia. The C3 photosynthetic pathway is prevalent, occurring in approximately two-thirds of …


Eurasian Watermilfoil: Status And Management In Iowa, Gary S. Phillips Dec 2001

Eurasian Watermilfoil: Status And Management In Iowa, Gary S. Phillips

Journal of the Iowa Academy of Science: JIAS

In 1993, Eurasian watermilfoil (Myriophyllum spicatum L.) was discovered in Crystal Lake, Hancock County, Iowa. During the next three years, new infestations were discovered by the Iowa Department of Natural Resources (IDNR) fisheries personnel in four Iowa lakes. In July 1996, a program was established by the IDNR to address the threat posed by Eurasian watermilfoil to Iowa's aquatic ecosystems. As part of the Eurasian Watermilfoil Program, statewide aquatic vegetation monitoring was begun to identify those lakes currently infested with Eurasian watermilfoil. Monitoring activities were conducted by IDNR field technicians during the summers of 1996 through 2000. During this time …


Non-Native Amphibians And Reptiles In Iowa, James L. Christiansen Dec 2001

Non-Native Amphibians And Reptiles In Iowa, James L. Christiansen

Journal of the Iowa Academy of Science: JIAS

Only a few species appear as introductions into Iowa in the last 30 years. The bullfrog, Rana catesbeiana, was systematically introduced along with fish stocked from hatcheries in the 1930s and this species continues to spread in northern Iowa where it poses a hazard to smaller frogs. Turtles sold as pets, primarily map turtles (Graptemys pseudogeographica and G. geographica) and red-eared turtles (Trachemys scripta) continue to be found in scattered ponds, usually rural, throughout the state. The eastern box turtle (Terrapene carolma) has been reported in or on the edge of most major Iowa cities even though no breeding population …


Index For The Journal Of The Iowa Academy Of Science Volume 108 And Erratum Dec 2001

Index For The Journal Of The Iowa Academy Of Science Volume 108 And Erratum

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Editorial Board & Iowa Academy Of Science Officers And Directors Dec 2001

Editorial Board & Iowa Academy Of Science Officers And Directors

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Introduced Fungi: Some Cause Significant Plant Disease Problems, Lois H. Tiffany Dec 2001

Introduced Fungi: Some Cause Significant Plant Disease Problems, Lois H. Tiffany

Journal of the Iowa Academy of Science: JIAS

Species of the three groups of fungi characterized here on the basis of their energy source acquisition have differing potentials for becoming problem organisms following introduction as alien fungi new to Iowa. The decomposer group of fungi that obtain an energy supply by action of extracellular enzyme activity on dead plant tissues typically have perennial mycelium, are cosmopolitan in distribution, and are unlikely to become problems even if established. The second group, the mycorrhizal/lichen group are highly specific in their relationships. The mycorrhizal fungus group have a potential for being introduced as mycorrhiza already established with the roots of particular …


More Than A Century Of Change In The Ames, Iowa Flora (1859-2000), William R. Norris, Mark P. Widrlechner, Deborah Q. Lewis, Jimmie D. Thompson, Richard O. Pope Dec 2001

More Than A Century Of Change In The Ames, Iowa Flora (1859-2000), William R. Norris, Mark P. Widrlechner, Deborah Q. Lewis, Jimmie D. Thompson, Richard O. Pope

Journal of the Iowa Academy of Science: JIAS

We compared two floras compiled in Ames, Iowa: (1) an "historic" flora based on two published floras (1871, 1890) and on 1450 herbarium voucher specimens of plants collected in Ames between 1859 and 1899, and (2) a "current" flora compiled by us during recent fieldwork (1990-2000). Our goals were to determine 1) long-term changes in composition (i.e., the proportion of native species) over time, 2) long-term changes in the abundance of individual plant species over time, and 3) the extent of gains and losses of native and non-native plant species. We found that the proportion of native species declined over …


Exotic And Invasive Woody Plant Species In Iowa, Donald R. Farrar Dec 2001

Exotic And Invasive Woody Plant Species In Iowa, Donald R. Farrar

Journal of the Iowa Academy of Science: JIAS

Seventy species and hybrids of exotic woody trees, shrubs, and vines have naturalized in Iowa. Nearly half of these species (31) have become invasive pests in parts of the state or have potential do so. Most of the seriously invasive species are spread by bird ingestion of whole fruits. Widespread dispersal by birds hinders eradication efforts and should be considered a trait indicative of potential invasiveness. The economic and ecological values of Iowa forests are seriously compromised by exotic invasive woody species, especially where forests recovering from cropland and pasture are dominated by exotic species. Thus, a simple measure of …


Forest Invasives In Iowa: Current Problems And Future Issues, John Walkowiak, John Haanstad Dec 2001

Forest Invasives In Iowa: Current Problems And Future Issues, John Walkowiak, John Haanstad

Journal of the Iowa Academy of Science: JIAS

Iowa's forest resources of primarily deciduous trees covers over 0.8 million hectares (2 million acres) of upland and floodplain sites too steep or too wet for traditional row crop agriculture. These limited natural forests along with urban trees and shelterbelts plantings of trees are critical for environmental and economic enhancement in the state. Although not yet established in the state, exotic insects, such as gypsy moth, Asian longhorned beetle, and pine shoot beetle, threaten native tree vitality. Established exotic diseases such as oak wilt and Dutch elm disease continue to plague the survival of Iowa's oak and elm resources, respectively. …


Back Cover Dec 2001

Back Cover

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Cover - Table Of Contents Dec 2001

Cover - Table Of Contents

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Purple Loosestrife: History, Management, And Biological Control In Iowa, Amy P. Wiebe, John J. Obrycki Dec 2001

Purple Loosestrife: History, Management, And Biological Control In Iowa, Amy P. Wiebe, John J. Obrycki

Journal of the Iowa Academy of Science: JIAS

Purple loosestrife (Lythrum salicaria) is an invasive plant species infesting wetlands in North America. Biodiversity and wetland habitat quality are reduced following purple loosestrife establishment. Several management tactics, including cultural, mechanical, and chemical controls, have had limited success in reducing the spread of purple loosestrife. Beginning in the 1990s, a biological control program has introduced several species of natural enemies from Europe that feed on purple loosestrife. Since 1994, Iowa State University has reared and released two species of beetles that feed on purple loosestrife, Galerucella calmariensis and G. pusilla. Biological control is one component of an integrated purple loosestrife …


History And Development Of The Eurasian Watermilfoil Program In Iowa, Gary S. Phillips Dec 2001

History And Development Of The Eurasian Watermilfoil Program In Iowa, Gary S. Phillips

Journal of the Iowa Academy of Science: JIAS

Following a concerted effort by citizens of the Iowa Great Lakes area to address the threat posed by Eurasian watermilfoil (Myriophyllum spicatum L.) to waterbodies in Iowa, the Iowa Eurasian Watermilfoil Law was passed in 1996 by the Iowa legislature. Passage of this law led to the establishment of the Eurasian Watermilfoil Program in July 1996 to address the requirements specified by this legislation. Since establishment of the Eurasian Watermilfoil Program, numerous activities have been carried out to address the threat posed to aquatic ecosystems by Eurasian watermilfoil. These include public awareness and education, boat access monitoring, aquatic vegetation monitoring, …


Ecological Problems With Iowa's Invasive And Introduced Fishes, Neil P. Bernstein, John R. Olson Dec 2001

Ecological Problems With Iowa's Invasive And Introduced Fishes, Neil P. Bernstein, John R. Olson

Journal of the Iowa Academy of Science: JIAS

Since the time of European settlement, at least 59 non-indigenous fish species have been introduced, reached, or moved within Iowa waters. At least 28 nonnative fish species have been introduced into, or reported from Iowa waters since settlement. Of that number, 10 are established at this time through natural reproduction. In addition, many species of native fishes have been translocated within the state, and we provide documentation for 31 of these species. Two translocated species, gizzard shad (Dorosoma cepedianum) and yellow bass (Marone mississippiensis), have had adverse impacts on Iowa's aquatic ecosystems. While many introductions are thought to be benign, …


Invasive Birds In Iowa: Status, Problems, And Threats, James J. Dinsmore Dec 2001

Invasive Birds In Iowa: Status, Problems, And Threats, James J. Dinsmore

Journal of the Iowa Academy of Science: JIAS

A total of 18 invasive bird species has been introduced into or have expanded their range to include Iowa. These include ten non-North American species, one North American species that has been displaced and now is established in Iowa, and seven native species that have been released to reestablish Iowa populations. Twelve of those are regularly occurring species in Iowa, and they comprise 3.0% (12 of 404) of the species known from Iowa and 5% (10 of 199) of Iowa's nesting avifauna. These percentages are similar to those found in neighboring states. Several more species are likely to become established …


Research Progress On Proton Exchange Membranes Of Fuel Cells, Jing-Rong Yu, Dan-Min Xing, Fu-Qiang Liu, Jian-Guo Liu, Bao-Lian Yi Nov 2001

Research Progress On Proton Exchange Membranes Of Fuel Cells, Jing-Rong Yu, Dan-Min Xing, Fu-Qiang Liu, Jian-Guo Liu, Bao-Lian Yi

Journal of Electrochemistry

The proton exchange membrane fuel cells(PEMFC) use proton exchange membranes(PEM) as their electrolytes. The performance of the PEMFC is strongly dependent on the characteristics of the PEM. In this paper, the requirements of the PEM utilized in the PEMFC were analyzed. The per_fluorinated, partially fluorinated and non_fluorinated PEM were introduced respectively. The structures, preparation, properties of the various types of PEM and their applications in the PEMFC were also discussed in detail.


New Progress Of Intrinsic Conducting Polymers' Application, Wan Chen, Cheng-Hao Liang, Yang Xie Nov 2001

New Progress Of Intrinsic Conducting Polymers' Application, Wan Chen, Cheng-Hao Liang, Yang Xie

Journal of Electrochemistry

As a kind of functional polymer, the intrinsic conducting polymer has the special chemical, electrochemical and optical properties. So it has wide application such as batteries, electromagnetic wave shielding, electroluminescent etc. Recent development and the problems of the intrinsic conducting polymers' application were briefly reviewed in this paper.


Thermal Effects On The Measurement Of Photocurrent At Anodic Films On Silver Electrode, Yuan Gu, Zhi Yu Jiang Nov 2001

Thermal Effects On The Measurement Of Photocurrent At Anodic Films On Silver Electrode, Yuan Gu, Zhi Yu Jiang

Journal of Electrochemistry

The influence of heat on the photocurrent of Ag electrode in alkaline solution was investigated by measuring photocurrent, photothermal signal and thermal current under the irraiation of laser beams with the wavelengths of 488 nm and 532 nm. It was found the photocurrent at the Ag 2O film was influenced by the temperature change at the electrode surface under the irradiation of light. During the electrochemical transfer between Ag, Ag 2O and AgO in the anodic film, the surface temperature changed obviously due to the different absorptance of the surface substances. It was suggested by comparing the voltammograms, photocurrent curves …


Corrosion Of Steel In Sea-Bottom Mud Of Nothern China Sea Area, Gong-Yu Guo, Jing-Lei Zhang, Bao-Rong Hou, Fang-Ying Yang Nov 2001

Corrosion Of Steel In Sea-Bottom Mud Of Nothern China Sea Area, Gong-Yu Guo, Jing-Lei Zhang, Bao-Rong Hou, Fang-Ying Yang

Journal of Electrochemistry

Corrosion experiments of A 3, 16Mn, 20 # as well as ZCE36_225 steel were carried out in southern Bohai sea and Qingdao sea areas. The sea_bottom mud in southern Bohai sea area is the sandy mud and that in Qingdao sea area is pure beach sand. In this experiment, the compareing test of two modes with electric connected and non_electric connected modes was carried out. The experiment results showed that: 1) the corrosion rate of steel in sea_bottom mud has a strong relation with mud types. The corrosion rates of steels in pure beach sand are much higher than those …


Study Of Hydrogen Diffusion Behavior In Hydrogen Storage Alloy Mlni_(3.75)Co_(0.65) Mn_(0.4) Al_(0.2) With Potential Step Method, Xian Xia Yuan, Nai Xin Xu Nov 2001

Study Of Hydrogen Diffusion Behavior In Hydrogen Storage Alloy Mlni_(3.75)Co_(0.65) Mn_(0.4) Al_(0.2) With Potential Step Method, Xian Xia Yuan, Nai Xin Xu

Journal of Electrochemistry

Potential step method was employed to study the hydrogen diffusion behavior in hydrogen storage alloy MlNi 3.75 Co 0.65 Mn 0.4 Al 0.2 with various depth of discharge(DOD) at ambient temperature and with 50%DOD at various temperatures. It was found that hydrogen diffusion cofficient in the hydrogen storage alloy increaes with the increase in DOD at ambient temperature. and for the alloy with 50%DOD,the hydrogen diffusion coefficient increases with the increase in temperature and the activation energy for hydrogen diffusion in the alloy is 19.87 kJ/mol.


Studies On The Anti-Corrosion Behavior Of Corrosion Inhibitor To The Ship Building Steel In Moist Air, Yong Tao Zhao, Jian Hua Wu, Jia Wang Nov 2001

Studies On The Anti-Corrosion Behavior Of Corrosion Inhibitor To The Ship Building Steel In Moist Air, Yong Tao Zhao, Jian Hua Wu, Jia Wang

Journal of Electrochemistry

The anti corrosion behavior of 907A steel, which were covered with thin inibitor layers in moist air, were simulated, The electrochemical measurements, including EIS method and the coulostatic method, were used to atmospheric corrosion monitor(ACM)under thin inhibitor layers to study the mechanism of rust preventiion. the results shown that the mechanism of inhibiting corrosion was different from the steel immersed in inhibitor solutin, the anodic reaction process under thin inhibitor layers had the advantage over that of cathodic for blocking the speed of corrosion. At the later stage of soaking, the blend feature due to the electrochemical process and the …


An Investigation Of Structural Properties Of Li-Al-Mixed Doped Spinels Materials Li_(1+X) Al_Ymn_(2-Y)O_4, Zi-Shan Zheng, Zi-Long Tang, Zhong-Tai Zhang, Wan-Ci Sheng Nov 2001

An Investigation Of Structural Properties Of Li-Al-Mixed Doped Spinels Materials Li_(1+X) Al_Ymn_(2-Y)O_4, Zi-Shan Zheng, Zi-Long Tang, Zhong-Tai Zhang, Wan-Ci Sheng

Journal of Electrochemistry

Al and Li elements were co_doped into host spinel lithium manganese oxide by a simple and economical preparation technology . There was an investigation of the influence of doped Al contents on the initial capacity and cycling performance of the materials. The investigation of the XRD patterns, the analysis of the SEM micrographs and the determination of IR spectroscopy showed that the particles of dopant materials are fine, narrowly distributed and well crystallized, and the bonds Mn_O are stronger than these of undoped materials. The resulted materials have a high initial capacity of 119 mAh/g and good cycling characterization. The …


Study On The Anticorrosion Of Ld-2 Compound Inhibitor On Reinforcing Steel In Seawater, Rong-Gui Du, Zhou-Cheng Wang, Ruo-Shuang Huang, Rong-Gang Hu, Bing Zhao, Jian-Guang Tan, Chang-Jian Lin Nov 2001

Study On The Anticorrosion Of Ld-2 Compound Inhibitor On Reinforcing Steel In Seawater, Rong-Gui Du, Zhou-Cheng Wang, Ruo-Shuang Huang, Rong-Gang Hu, Bing Zhao, Jian-Guang Tan, Chang-Jian Lin

Journal of Electrochemistry

The effect of LD_2 compound inhibitor developed in our laboratory on its anticorrosion action on the reinforcing steel in concrete immersed in seawater was shown in this paper. The corrosion behavior of the reinforcing steel in seawater was studied using electrochemical techniques and immersion tests. The polarization curve of the reinforcing steel immersed in seawater showed the free corrosion potential of the steel increased by 0.220 V (vs. SCE), and the corrosion current decreased by two orders of magnitude by adding 25 g·L -1 compound inhibitor to the seawater. The potentiodynamic anodic polarization curve of reinforcing steel in the seawater …


Study On Electrochemical Behavior Of Copper In Nh_3·H_2o Solution Medium Including K_3 During Cmp, Yue Hua Hu, Han Wei He, Uang Ke Nong H Nov 2001

Study On Electrochemical Behavior Of Copper In Nh_3·H_2o Solution Medium Including K_3 During Cmp, Yue Hua Hu, Han Wei He, Uang Ke Nong H

Journal of Electrochemistry

Influence of medium pH value and passivator concentrations on the copper passivation and CMP process were studied by electrochemical measurement technologies, relations of the film thickness and tightness with polishing process and polishing rates were investigated. Electrochemical variables influencing polishing process and rates were found out. Electochemical mechanism of polishing processes were explained by corrosion potential and corrosion current density. A recipe of K 3 as passivator and nano sized γ Al 2O 3 as abrasives in medium of NH 3·H 2O solution was confirmed reasonable. It is shown that the conditions of polishing process to be controlled are 10 …


The Influence Of Synthesis Conditions On The Electrochemical Properties Of Spinel Limn_2o_4, Jun Feng Xu, Zhi Yu Jiang Nov 2001

The Influence Of Synthesis Conditions On The Electrochemical Properties Of Spinel Limn_2o_4, Jun Feng Xu, Zhi Yu Jiang

Journal of Electrochemistry

The electrochemical properties of spine LiMn 2O 4 synthesized via a solid state reaction were investigated. Electrolysis MnO 2(EMD), Li 2CO 3,LiOH and LiNO 3 were used as the initial materials. It was found that the electrochemical properties of LiMn 2O 4 were strongly influenced by the synthesis conditions. The LiMn 2O 4 samples prepared via the reaction of EMD and LiNO 3 showed the best properties for a lithium ion intercalation reaction. The procedure includes two steps: pretreatment at 280 ℃ for 6 hours to initiate the permeation of melting LiNO 3 into the micropores of EMD particles, followed …