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Articles 77881 - 77910 of 78513
Full-Text Articles in Entire DC Network
Some Consequences Of The Decomposition Of Organic Matter In Lake Nitinat, An Anoxic Fjord, Francis A. Richards, Joel D. Cline, William W. Broenkow, Larry P. Atkinson
Some Consequences Of The Decomposition Of Organic Matter In Lake Nitinat, An Anoxic Fjord, Francis A. Richards, Joel D. Cline, William W. Broenkow, Larry P. Atkinson
CCPO Publications
Observations in Lake Nitinat, an anoxic fjord on Vancouver Island, British Columbia, indicate that the large accumulations of ammonia, carbonates, phosphates, silicates, and sulfides in the deep water are the result of oxidative and fermentative decomposition of organic matter of planktonic origin, the reduction of sulfate ions, hydrolytic or other non-oxidative release (in the case of silicates), and the solution of carbonates (which also increases the alkalinity). Ammonia, sulfides, and silicates accumulate in the sulfide zone in direct proportion to each other, but some of the phosphate is probably released from the organic matter earlier than the other components, and …
I. An Investigation Of The Organic Compounds In The Media And Mycelium Of Naucoria Confragosa. Ii. Study Of The Extra-Cellular Pigments Of An Unknown Fungus, Yueh-Tsun Chen
Masters Theses
"The fungal metabolites excreted into the culture fluid by basidiomycetes growing on synthetic glucose media as well as formed in the mycelia of the organisms were investigated in this thesis. Earlier unpublished work had shown that Maucoria confragosa excreted into the medium compounds which were thought to be phenols. Insufficient material was recovered from an ethyl acetate extract of the medium in the present study for further investigation. Colorimetric methods were employed both for the quantitative estimation of reducing sugar not consumed by the microorganisms as well as for a measure of the total organic solids present in the spent …
The Distribution Of Phytoplankton Along A 140 Mile Transect In The Chesapeake Bay, Harold G. Marshall
The Distribution Of Phytoplankton Along A 140 Mile Transect In The Chesapeake Bay, Harold G. Marshall
Biological Sciences Faculty Publications
The composition of phytoplankton progressively changed in the surface samples taken between Norfolk, Virginia and Cambridge, Maryland. These was an inverse relationship between the numbers of phytoplankters and zooplankters in the transect samples. Vertical stratification of the plankton was studied at two 24-hr, stations at the Great Wicomlco and Patuxent Rivers. The vertical centers of zooplankton and phytoplankton populations fluctuated over the study period and evidence is given to support a grazing phenomenon. Large concentrations of nannoplankters were found in all the plankton samples taken and is attributed to the collection procedure using the Van Dorn sampler.
The Annual Distribution And Stratification Of Phytoplankton At Aurora Lake, Portage County, Ohio, Harold G. Marshall
The Annual Distribution And Stratification Of Phytoplankton At Aurora Lake, Portage County, Ohio, Harold G. Marshall
Biological Sciences Faculty Publications
A 13-month study of a hard-water lake in northeast Ohio has provided a quantitative and qualitative record of the seasonal changes of the phytoplankton. Maximum production occurred during the summer and winter periods. The summer pulse was dominated by the cyanophyte species: Microcystis aeruginosa, Anabaena spiroides, A. circinalis, and Aphanizomenon flosaquae. The dominants of the winter pulse were the diatoms Fragilaria crotomensis and Asterionella formosa, which formed separate peaks under an ice cover in December and January, respectively. The January development extended into March with the highest concentrations for the year Being reached at approximately …
Use Of Neutron Activation Analysis In The Study Of Biological Disposition Of Antimony Compounds, Moustafa Mahmoud Mansour
Use Of Neutron Activation Analysis In The Study Of Biological Disposition Of Antimony Compounds, Moustafa Mahmoud Mansour
Archived Theses and Dissertations
No abstract provided.
Available Water Supply Of The Las Vegas Ground-Water Basin Nevada, Glenn Thomas Malmberg
Available Water Supply Of The Las Vegas Ground-Water Basin Nevada, Glenn Thomas Malmberg
Publications (WR)
The Las Vegas ground-water basin as described in this report includes the southern part of Indian Spring Valley, Three Lakes Valley, the northern half of Ivanpah Valley, and Las Vegas Valley. These valleys in part are inferred to form a hydrologic unit that includes an area of about 3,000 square miles in the southern part of Clark County, Nev.
The valleys forming the Las Vegas ground-water basin are broad structural depressions surrounded by mountains. The climate of the region is arid, and precipitation in the basin lowlands rarely exceeds 5 inches per year. Drainage is interior except for occasional Hood …
Östliche Gruppe Der Monolistrini (Crust., Isoopoda): Ii.Biologischer Teil, Boris Sket
Östliche Gruppe Der Monolistrini (Crust., Isoopoda): Ii.Biologischer Teil, Boris Sket
International Journal of Speleology
Following the first systematic part, in this paper the author describes the biological observations made on these Isopod Crustaceans of underground waters. The different sexual characters of the particular groups and the related differences in the behaviour before copulation are described. During the embryonic and larval development small differences between sub-genus are reported. To the differences in Caecospaeroma (according to Daum) the first and second “mancastadium” and another “postmanca stadium” with pereiopods VII not wholly formed have to be added. The author describes the growth of the different parts of the corps and the extremities, comprising the sexual characters.
Fluorescein As A Reagent In A Spectrophotometric Determination Of Micro-Amounts Of Iodine: Application To Glucose Determination, Donald Eugene Braun
Fluorescein As A Reagent In A Spectrophotometric Determination Of Micro-Amounts Of Iodine: Application To Glucose Determination, Donald Eugene Braun
University of the Pacific Theses and Dissertations
The increasing awareness of the close inter-relationships between biological activity and chemical reactions has resulted in a rapidly growing pursuit of biochemical knowledge. Research in the related fields of medicine, virology, pharmacy, and biophysics is expanding at a rapid rate. Problems related to food production for an exploding population, space explorations, world health issues, the utilization of the resources of the oceans, and the proper employment of energy sources have spurred man to delve deeper into the secrets of creation. The mysteries of life itself are slowly being revealed through finding in egentic studies.
With this ever expanding biochemical and …
Anomers Of D-Galactosamine Benzoates, Robert Stanley Strong
Anomers Of D-Galactosamine Benzoates, Robert Stanley Strong
University of the Pacific Theses and Dissertations
D-Galactosamine has been known as one of the rarer amino sugars, occurring widely distributed in small concentrations in living organisms. The biological importance of D-galactosamine and its derivatives was thought to justify a study of the chemical properties of this group of compounds. As a result of this study the reactions of D-galactosamine have been found to differ more than previously thought from those of D-glucosamine, the more common amino sugar
For this investigation D-galactosamine hydrochloride was isolated from chondroitin sulfate, a polysaccharide obtained from the cartilaginous tissues of animals. This was changed by appropriate reactions to the 1,3,4,6-tetra-0-benzoyl-N-carbobenzoxy-α-β-D-galactosamine (III). …
Derivatives Of Benzyl N-Benzoyl-A-D-Glucosaminide, Kenji Miyai
Derivatives Of Benzyl N-Benzoyl-A-D-Glucosaminide, Kenji Miyai
University of the Pacific Theses and Dissertations
Within the past few decades, interest in the field of aminosugar chemistry has been stimulated to a remarkable degree and the discovery and syntheses of a wide range of new aminosugars of differing types, for example of two monoamino-tetroses (12,19), nineteen monoamino-pentoses, two diamino-pentoses, thirty-three monoamino-hexoses, and eighteen diamino-hexoses (20) have been accomplished. It is well undterstood that the aminosugars, significant constituents in mnay biologically important materials (11), consist of substances that may be regarded a teh condesation products of an amine and a carbohydrate. Falling into this category are the 2-amino-hexoses which may be derived conceptually as the condensation …
Contribution À L'Étude De La Biologie D'Asellus Cavaticus Leydig (Note Préliminaire), Jean-Paul Henry
Contribution À L'Étude De La Biologie D'Asellus Cavaticus Leydig (Note Préliminaire), Jean-Paul Henry
International Journal of Speleology
The cavernicole asellid Asellus cavaticus Leydig has been reared in our laboratory for more than twenty months, permitting us to give some data on the sexual cycle of this species. Females provided with brood pouches seem to be more numerous in the spring, as is the case with the subterranean amphipod Niphargus virei Chevreux. The average length of the incubation period seems much shorter than that of other troglobitic species such as Niphargus virei Chevreux or Caecosphaeroma burgundum Dollfus, so that the life cycle of our species is nearer to that of epigean Asellus. The number of young per …
Les Chauves-Souris Cavernicoles De La Suisse, Villy Aellen
Les Chauves-Souris Cavernicoles De La Suisse, Villy Aellen
International Journal of Speleology
Bats, familiar to speleologists, play an important part in animal ecology in caves. Indirectly by their guano, they provide a source of food for numerous cave-dwelling animals and directly, by their own more or less constant presence. 26 species of bats are known from Switzerland, 15 of which occur in caves. Miniopterus schreibersi is considered the only true cave-dweller. The exact distribution of the rare species, including those occurring outside caves, is found in the text and is also indicated on the accompanying maps.
Faune Des Eaux Souterraines Saumâtres De L'Asie Centrale, J. A. Birstein, S. I. Ljovuschkin
Faune Des Eaux Souterraines Saumâtres De L'Asie Centrale, J. A. Birstein, S. I. Ljovuschkin
International Journal of Speleology
In the cave Kaptar-Khana (south-western Turkmenistan) was discovered a lake filled with water with a salinity of 11,68‰. This lake is inhabited by a fauna of marine origin - Foraminifera (three species), Molluscs (Pseudocaspia ljovuschkini sp.n.), Harpacticoida (genera Ectinosoma, Schizopera and Nitocra), Isopoda (Microcharon halophilus sp.n.) and possibly Nematoda (Oncholaimidae). The majority of the discovered species are related to species of circum-Mediterranean origin. Geological data do not permit to consider this fauna as a relict of any of the tertiary seas. The same applies to all other cases when animals of marine origin were discovered …
Recherches Phréatobiologiques Ii: La Capture Des Niphargus Adultes Par Le Procéde Des Sondages Karaman-Chappuis. Les Crues Et La Biocenose De La Nappe Phréatique, Constantin Motas, Eugène Serban
Recherches Phréatobiologiques Ii: La Capture Des Niphargus Adultes Par Le Procéde Des Sondages Karaman-Chappuis. Les Crues Et La Biocenose De La Nappe Phréatique, Constantin Motas, Eugène Serban
International Journal of Speleology
The present note calls into question the opinion of different authors concerning the presence or lack of adult Niphargus near the phreatic table (superior layer of phreatic water) in zones prospected by Karaman-Chappuis method. Our investigations have proved the reason for which Niphargus adults were less frequent in the superior layer of the phreatic water is rather concerned with our investigation means - which are very approximate - than with the ecological or ethological requirements of these animals. The assertion that the phreatic fauna performs downward migrations during the floods must be considered as doubtful. During floods it is impossible …
Beiträge Zur Kenntnis Der Brunnenfauna Im Tal Des Flusses Bela Reca (Rumänien), Constantin Motas, Iosif Capuse
Beiträge Zur Kenntnis Der Brunnenfauna Im Tal Des Flusses Bela Reca (Rumänien), Constantin Motas, Iosif Capuse
International Journal of Speleology
After an introduction, comprising a historical summary on the researches on well fauna, a description of the study area in which 13 water wells have been investigated is given. The authors explain the adopted working method and indicate the physical and chemical characteristics of the waters (temperature, pH, alkalinity, hardness, O2-content, fixed residuum, suspended matter, N2O5, P2O5, NaCl, Ca, Fe). The fauna of the wells of Mehadia (see systematic part) is composed of 34 species: 1 Triclade, 3 Oligochaeta, 2 Gastropods, 5 Cladocera, 1 Ostracod, 3 Copepods, 4 Isopods, 2 …
Daten Zur Kenntnis Der Algenflora Der Höhle Kölyuk Von Mánfa, George Claus
Daten Zur Kenntnis Der Algenflora Der Höhle Kölyuk Von Mánfa, George Claus
International Journal of Speleology
The Kolyuk cave lies in the southern part of Hungary in the Mecsek Mountains, about 3 km. in distance from the village of Mànfa. The material accepted for investigation originated from a recently discovered and until now completely entombed part of the cave. It was collected by the geologist Gàbor Magyari and consisted of material scraped from the walls and ceiling of a cavity in the cave, which could be reached only by underwater swimming. From these scrapings cultures were installed with sterile Knopp solution and after the algae present in the collection reproduced, a diversified flora developed which consisted …
Preliminary Note On The Algae Of Crystal Cave, Kentucky, J. P. Nagy
Preliminary Note On The Algae Of Crystal Cave, Kentucky, J. P. Nagy
International Journal of Speleology
Collections of a preliminary type carried out in Crystal Cave, Kentucky, resulted in the identification of seven algal taxa. A Chamaesiphon (Dermocarpales) and an Asterocytis (Bangioidea) are reported for the first time from a speleo-environment. As no correlation could be found among the algae occurring in Crystal Cave and those of nearby Mammoth Cave the conclusion is reached that the cave algal floras do not originate from the algal vegetation of the surface but may have gotten into the caves at the time of the latter’s formation.
Algological Investigations In Mammoth Cave, Kentucky, H. J. Jones
Algological Investigations In Mammoth Cave, Kentucky, H. J. Jones
International Journal of Speleology
Algological investigations carried out in the Mammoth Cave, Kentucky, revealed the presence of twenty-seven taxa representing all divisions of the Algae except the Pyrrhophyta and Phaeophyta; diatoms although observed in the samples were not dealt with in the present paper. One species, Oscillitoria clausiana spec. nov. and a form Lyngbya pusilla fa. tenuior fa. nov., both belonging to the Cyanophyta are new to science. In addition, several other rare and interesting algae were found. A comparison is made between the algal flora of the Mammoth Cave and algae found in several European caves. The ecology of the cavernicole algae is …
Diatoms From Mammoth Cave, Kentucky, Sam L. Van Landingham
Diatoms From Mammoth Cave, Kentucky, Sam L. Van Landingham
International Journal of Speleology
Samples collected in Mammoth Cave, Kentucky, revealed the presence of a diversified but not too abundant diatom community in the cave. As the material was not subjected to culturing experiments but was investigated immediately after arrival, both in native and permanent preparations, it was possible to: 1. ascertain that the majority of the diatoms contained well developed, apparently healthy and functioning chloroplasts and 2. to get a rough estimate of the actual number of specimens present in a microhabitat. The identifications resulted in the recognition of 16 diatom taxa of which possibly 4 are new to science. Further studies are, …
Limnology Of Carbonate – Bicarbonate Lakes In Nebraska, D. B. Mccarraher
Limnology Of Carbonate – Bicarbonate Lakes In Nebraska, D. B. Mccarraher
Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts
The relation between chemical, physical and biological indices was examined in 1,640 sandhill lakes during the years of 1954 to 1963. Sandhill lakes are formed by either (1) wind deflation basins and closed drainages or (2) exposed ground water table basins. Topography of the 20,000 square mile sandhill region is primarily stabilized dune sand interspersed with wet meadows and pine - cedar - oak river drainage systems. Two-thirds of the area is dune sandhills and one-third occupied by basins, valleys and lakes.
All of the lakes are comparatively shallow, the deepest lake being Blue Lake with 13.8 feet. The average …
Intramolecular Spin-Orbit Coupling In Naphthalene Analogs, Francis Elliott Shoup Iii
Intramolecular Spin-Orbit Coupling In Naphthalene Analogs, Francis Elliott Shoup Iii
Chemistry and Chemical Biology ETDs
The objective of this study was to gain additional insight into the phenomenon of spin-orbit coupling in molecules by examining the intramolecular mechanisms responsible for the phosphorescence of certain types of molecules. Spectrocopic investigations of a series of aromatic hydrocarbons, aromatic heterocyclics, and some of their halogen derivatives are reported. Experimental measurements included absorption spectra, total emission spectra, polarized emission spectra, obtained by the method of photoselection, and radiative lifetimes. It was found that chlorine substitution in naphthalene, quinoline, and quinoxaline has the effect of enhancing the transition probability for radiative transitions from the Blu component of the 3 …
Crystal Field Splitting In Rare Earth Chelates, Walter George Perkins
Crystal Field Splitting In Rare Earth Chelates, Walter George Perkins
Chemistry and Chemical Biology ETDs
Investigations of ligand field effects in the spectra of trisdibenzoylmethide, trisbenzoylacetonate, and trisacetylacctonatc chelates of trivalent ytterbium and thulium are reported. Chelate absorption and luminescence spectra corresponding to intra-4f electronic transitions exhibit line splittings similar in magnitude to the crystal field splitting observed in the spectra of inorganic complexes of the rare earth ions.
Absorption spectra of carbon tetrachloride solutions of all the chelates studied were measured in the visible and near infrared regions. Each ytterbium chelate exhibits an absorption band at 9800A, consisting of three well-resolved peaks. Thulium intra-4f absorption bands appear at 4700A, 6800A, 8000A, 12000A, and 17000A. …
The Radiochemical Purification Of Europium And A Study Of The Nuclear Properties Of Eu157, Eu158 And Eu159, William Richard Daniels
The Radiochemical Purification Of Europium And A Study Of The Nuclear Properties Of Eu157, Eu158 And Eu159, William Richard Daniels
Chemistry and Chemical Biology ETDs
Chemical procedures have been developed for the rapid preparation of radiochemically pure europium sources from rare earth mixtures and from fission products. Unpurified mixtures of the mono- and dirp(l,1,3,3- tetramethylbutyl)phenyl 1 esters of orthophosphoric acid are used to extract rare ei1arths in the (III) oxidation state away from europium in the (II) oxidation state. Europium sources can be prepared in about 30 min-11tes.
A slowr chemical procedure for the preparation of europium sources which are both radiochemically pure and mass free has also been developed. Di(2-ethylhEtxyl) orthophosphoric acid is used to separate europium from yttrium, which has a high fission …
Government Research (2nd Bird Control Seminar 1964), Clarence Faulkner , A. B. Stevenson , Carlton Herman
Government Research (2nd Bird Control Seminar 1964), Clarence Faulkner , A. B. Stevenson , Carlton Herman
Bird Control Seminars Proceedings
Papers include:
Control Methods and Pesticide Problems
Canadian Programs
Disease as a Factor in Bird Control
Academic Aspects Of Bird Control (2nd Bird Control Seminar 1964), William B. Jackson , Mel Dyer, Walter Howard
Academic Aspects Of Bird Control (2nd Bird Control Seminar 1964), William B. Jackson , Mel Dyer, Walter Howard
Bird Control Seminars Proceedings
Papers include:
Dr. William B. Jackson, Bowling Green State University - Undergraduate Preparation
Dr. Mel Dyer, Ontario Agricultural College, Guelph, Canada - Approaches to Research
Dr. Walter Howard, University of California, Davis - Some General Remarks Regarding Bird Control
Presentation of Specific Problems
Public Health Aspects Of Bird Control, William B. Jackson, Ralph Masterson, Paul Schnurrenberger, D. O. Jones, Roderic Jones, John Morley, George Mowrey
Public Health Aspects Of Bird Control, William B. Jackson, Ralph Masterson, Paul Schnurrenberger, D. O. Jones, Roderic Jones, John Morley, George Mowrey
Bird Control Seminars Proceedings
The first session; papers include:
Animal Diseases in General
Public Health Aspects of Bird Control or Zoonoses
Public Relations
Sanitation
Commercial Operations Session (2nd Bird Control Seminar), Lee Truman, Phil Spear, Jim Steckel, Harlan Shuyler
Commercial Operations Session (2nd Bird Control Seminar), Lee Truman, Phil Spear, Jim Steckel, Harlan Shuyler
Bird Control Seminars Proceedings
Third session; papers include:
New Problems
New Materials
Preparation of Materials and New Techniques
Community Control Programs
Proceedings: Second Bird Control Seminar (1964) -- Contents And Schedule
Proceedings: Second Bird Control Seminar (1964) -- Contents And Schedule
Bird Control Seminars Proceedings
BOWLING GREEN STATE UNIVERSITY, BOWLING GREEN, OHIO 1964
In cooperation with:
U. S. Fish a Wildlife Service, Ohio Pest Control Association, Toledo Department of Health, Economic Biology Curriculum, Bowling Green State University
Note to the reader:
These proceedings were taken "verbatium" on stenotype machine by the Hammock, Pace, and LaMotte Company of Columbus, Ohio. Several of the speakers did not use prepared texts, and one session made extensive use of slides. Therefore, many parts of the proceedings make somewhat unusual or seemingly disjointed reading. This is caused by the fact that we are unable to incorporate inflec¬tions of voice, mood, …
Metabolism Of Thiamine And The Effect Of Some Antagonists, Russel M. Bender
Metabolism Of Thiamine And The Effect Of Some Antagonists, Russel M. Bender
Theses and Dissertations
To investigate the possibility that thiamine has more than one vital role in the mammalian system, it was decided to use the antagonists pyrithiamine and oxythiamine, and to utilize carbon-14 labeled compounds to more effectively study the vitamin and the above-named antagonists. To make it more effective, we felt that perhaps differences between the localization of oxythiamine and pyrithiamine could be detected in the brain. We also considered and tested the possibility that either or both of the antagonists would alter the localization of thiamine. Essentially, two procedures were used in this study. One was a counting method and the …
The Reaction To Ketoacylhydrazones With Lead Tetraacetate, Lavern M. Weisenberger
The Reaction To Ketoacylhydrazones With Lead Tetraacetate, Lavern M. Weisenberger
Masters Theses
Introduction
It has been shown that ketohydrazones react with lead tetraacetate to give azoacetates in good yields (11) according to the following equation:
R2C=N-NH-R + Pb(OAc)4 → R2C(OAc)-N=N-R + Pb(OAe)2 + HOAc
The reaction of the structurally related 4,4- disubstituted ketosemicarbazones with lead tetraacetate quite unexpectedly gave carbamates in good yields (10) presumably according to the following equation:
R2C=N-NH-Co-NR2 + Pb(OAc)4 → R2C-O-CO-NR2 + N2 + Pb(OAc)2 + HOAc
CO
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CH3