Showing papers on "Water environment published in 1983"

Insect Species Diversity as a Function of Environmental Variability and Disturbance in Stream Systems

Abstract: Thienemann (1954) observed that the number of species inhabiting a given locality is highest in areas which have persisted largely unchanged for a long time and are characterized by diverse and predictable (i.e., not deviating substantially from the long-term norm) environmental conditions. The rhithron (i.e., the habitat of cold, rubble-bottom streams often found in the middle and upper reaches of river systems) epitomizes the ideal running water environment for co-existence of many species (Illies, 1969), most of which are usually insects (Hynes, 1970).

Studies on Anhydrobiosis of Pratylenchus thornei.

Abstract: Large populations of Pratylenchus thornei, a winter pest of cereals, legumes, and potatoes in the northern Negev region of Israel, survive 7-8 months of summer drought and return to full activity at the beginning of the rainy season. To demonstrate that it survives the summer in an anhydrobiotic state, all developmental stages of P. thornei were exposed to gradually reduced relative humidity (RH) using glycerin water solutions. At 97.7% RH the nematodes were coiled and able to survive exposure to 0% RH. About 40% of artificially desiccated nematodes could be reactivated by gradually increasing the humidity to the final water environment. Desiccated nematodes could withstand temperatures up to 40 C. Reactivated individuals showed intestines apparently devoid of reserve materials. Only 3% survived three cycles of desiccation and reactivation. P. thornei reactivated after anhydrobiosis multiplied twice as much within Vicia sativa roots as did fresh nematodes.

Devonian trilobites of the southern Cantabrian Mountains (northern Spain) with a systematic description of the Asteropyginae

Abstract: This paper shows the results of a research into the Devonian trilobites of the southern Cantabrian Mountains. The systematics of the most common group, the subfamily of the Asteropyginae, forms the major part of this work. More than 50 species, belonging to sixteen (sub)genera are distinguished; thirteen species are newly described and four species are redescribed. It turned out that many species recently described from Aragon, Asturias and the Armorican Massif also occur in the southern Cantabrian Mountains. The find of Metacanthina lavidensis n.sp. in the La Vid Fm. makes it probable that the genus Metacanthina descended from Pilletina in the Siegenian. The morphological features and age of Delocare? dalii n.sp. support the theory that Delocare descended from Paracryphaeus in the Siegenian. A first time a Neocalmonia species N. cantabrica n.sp.) has been found outside Afghanistan. Its morphological features and occurrence in the Huergas Fm. indicate it descended from the genus Bradocryphaeus in the lowermost Givetian. The genus Neocalmonia therefore originated in Europe. The find of G. (Greenops) ultimus n.sp. in the Portilla Fm. prolongs the known existence of the genus Greenops far into the Frasnian. Bradocryphaeus sexspiniferus n.sp. is the first species of Frasnian age with six pairs of lateral pygidial spines which has been found outside Afghanistan. Meraspides of Kayserops obsoletus are discussed. Apart from the Asteropyginae more than 60 other trilobite species are mentioned per stratigraphic level and for the greater part depicted. In the Devonian the trilobite faunas of the Asturo-Leonese and Palentian Basins show a gradually growing difference. In the Gedinnian and Siegenian the difference is not very marked. In the Emsian the Palentian Basin yields, beside common species with the Asturo-Leonese Basin, many elements which indicate a deeper water environment (Odontochile, Reedops, Cheirurus (Pilletopeltis), Xiphogonium and Astycoryphe). In the Middle and Upper Devonian the two basins do not have any species in common. In the Asturo-Leonese Basin Asteropyginae and some subspecies of the “North American” Phacops rana dominate; in the Palentian Basin a restricted fauna occurs which indicates a deeper water environment (with Eocryphops, Paraaulacopleura and Trimerocephalus). It has been attempted to correlate the deposits in both basins with other areas (a.o. Aragon and the Armorican Massif). Most striking are the correlations which have been made of the Requejada Member (Abadia Fm.; Palentian Basin) with the upper part of the Faou Fm. (Armorican Massif) and of the upper part of the limestone member of the La Vid Fm. (Asturo-Leonese Basin) with the lower part of the Mariposas Fm. (Aragon). As a result of correlations with Asteropyginae within the Ibero-Armorican region a provisional zonation has been designed. It turned out that the Asteropyginae, which originated in the Lower Gedinnian in Europe (or northern Africa) and extended in the Middle Devonian to the east and the west, were restricted to the tropical part of the southern hemisphere.

Water-proof photographic camera with an automatic focusing device

Abstract: In a water-proof photographic camera with an automatic focusing device, a taking lens will be moved to a best-in-focus position by the automatic focusing device when it is detected that the camera is in air enrivonment, and to a fixed focusing position corresponding to a value of camera-to-object distance that is expected to be most frequently used in underwater photography or a value of distance in accordance with an available amount of light emitted from an electric flash device when it is detected that the camera is in a water environment.

Methods for recovering viruses from the water environment.

Abstract: The major preoccupation of those who study viruses in water has been with the development of methods capable of detecting viruses in large volumes of water. This chapter focuses on the most promising and extensively used methods and the principles upon which the methods are based. Methods involving virus adsorption-elution from microporous filters continue to be the most promising and useful methods for concentrating viruses from large volumes of water. Positively charged microporous filters have been used recently to recover small amounts of seeded poliovirus and bacteriophages from drinking water. Viruses have been concentrated successfully from sewage and water by adsorption onto and elution from insoluble polyelectrolytes. For detection of viruses in small amounts of fluids, a one-step adsorption-elution procedure is often used. Methods involving microporous filters are the only ones which have been shown useful for concentrating viruses from large volumes of tapwater, sewage, seawater, and other types of natural waters.

Thermostatic fishing device

Abstract: A fishing assembly including a line, a sinker, a fish snare which may include a hook, bait and/or lure, and a leader for said snare, and including a bimetallic member, adapted for changing state in response to the temperature of the water environment in which said assembly is located, is arranged for determining the depth of said line to its junction with said leader whereby said leader is positioned in water of a predetermined temperature.

Consistency Tests of Acoustic Propagation Models

Abstract: : Three wave-theory models (NM, FFP, PE) and one ray model are applied to four different ocean environments: a range-dependent surface duct, a deep- water environment with a homogeneous bottom, a shallow-water environment with a homogeneous bottom, and a sloping-bottom environment with a layered bottom. The consistency among the acoustic models is clearly demonstrated through the agreement between model results for the various test problems.

Production of precipitation strengthening type ni-base alloy

Abstract: PURPOSE: To produce a precipitation strenthening type Ni-base alloy by subjecting an alloy having the compsn. consisting of C, Si, Mn, Fe, Cr, Ti, Nb, Al, P, S, N, Ni, etc. to hot working and heat treatment under adequate conditions. CONSTITUTION: An alloy having the compsn. consisting of ≤0.05% C, ≤0.50% Si, ≤1.0% Mn, 5.0W10.0% Fe, ≤(18W30%) Cr, ≤0.50% Ti, 2.0W5.0% Nb, ≤0.40% Al, ≤0.015% P, ≤0.005% S, ≤0.03% N and further, if necessary, consisting of ≤7.0% Mo and/or ≤0.1% total of at least one kind among REM, Mg, Ca and Y and the balance Ni (but at least ≥50%) is subjected to hot working of ≥50% draft at 800W1,200°C and after the alloy is held for 5minW5.0hr at 1,000W1,200°C, the alloy is cooled at a cooling rate of air cooling or above and is then subjected to ≥1 time of an aging heat treatment for 1.0W150hr at 550W800°C. The precipitation strengthening type Ni-base alloy having excellent resistance to stress corrosion cracking under high-temp. and high-pressure water environment is obtd. COPYRIGHT: (C)1985,JPO&Japio

Influence of Cl^- Concentration on Corrosion Fatigue Crack Growth of an Austenitic Stainless Steel

Abstract: Corrosion fatigue crack growth rate of an austenitic stainless steel (SUS304) was measured in Cl- containing water. Acceleration mechanisms of crack growth in corrosive environment were discussed, and an acceleration of da/dN in SUS3O4 was compared with that in a high-tension steel (HT55). The first step acceleration of da/dN in water environment from that in dry air was due to the reverse slip suppressing effect induced by water molecule adsorption. The second step acceleration at a low frequency (f=0.1Hz) was due to hydrogen embrittlement of plasticity-induced martensite formed at crack tips. In 3% NaCl solution at f=0.1Hz, the acceleration by stress-assisted dissolution was also observed. The crack opening ratio (U) was independent of Cl- concentration as well as of cycle frequencies. The acceleration of da/dN in SUS304 amounted to 9.2 times that in HT55, and a water environment sensitive crack growth behavior under cyclic stresses was clear. However, there existed a threshold ΔK to commencing to accelerate da/dN from that in air, and the acceleration in HT55 exceeded that in SUS304 at f=5Hz near ΔKth.

Slow crack growth in spinel in water

Abstract: Magnesium aluminate spinel was tested in a water environment at room temperature to establish its slow crack-growth behavior. Ring specimens with artificial flaws on the outside surface were loaded hydraulically on the inside surface. The time to failure was measured. Various precracking techniques were evaluated and multiple precracks were used to minimize the scatter in the static fatigue tests. Statistical analysis techniques were developed to determine the strength and crack velocities for a single flaw. Slow crack-growth rupture was observed at stress intensities as low as 70 percent of K sub c. A strengthening effect was observed in specimens that had survived long-time static fatigue tests.

Observational Study On Thermal Flow And Condensation Of Injecting Steam From Various Submerged Orifices

Abstract: It has been recognized that the steam accumulator plays an important role as one of thermal energy storage system and was used at hospitals, hotels and food factories in recent years. Experiments have been carried out to investigate direct contact condensation of saturated steam into a quiescent subcooled water environment. They were performed for subcooling from 20 - 70°C, for atmospheric pressure, and for various type of orifice ( single-orifice, multi-orifice and porous-disc-orifice ). The phenomena were observed by means of high speed shadowgraphy using a rotating prism camera. The phenomena were also visualized by techniques of liquid crystal using a still camera. The effect of bulk temperature in a water tank and the difference among a single-orifice, a multi-orifice and porous-disc-orifice were discussed and good predictive results for the visualization of thermal flow in a quiescent subcooled water environment were obtained.© (1983) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The reactivity of p-nitrophenyl esters with surfactants in apolar solvents. V. p-Nitrophenyl acetate in benzene solutions of butane-1,4-diamine bis(dodecanoate)

Abstract: The rate of decomposition of p-nitrophenyl acetate in benzene in the presence of butane-1,4-diamine bis(dodecanoate) (budb) has been measured at temperatures between 333 and 353 K. The data fit a rate equation which consists of a term arising from micellar catalysis and a term arising from a bimolecular reaction between the ester and the components of budb. Arrhenius parameters have been estimated for the two reaction modes and compared with newly extended data for the similar reaction with dodecylammonium propionate (dap). 13C n.m.r. analysis of the products from there action of p-nitrophenyl propionate in the presence of dap has revealed that the amide is formed by an aminolysis reaction. The decrease in reaction rate observed with increasing water concentration is interpreted in terms of a biphasic water environment.

Water as a Learning Environment for Facilitating Gross Motor Skills in Deaf-Blind Children

Abstract: An overview of a specialized pool program for deaf-blind children is presented in which the goal is to facilitate the achievement of gross motor, social and communication skills in a water environment, with subsequent generalization of these skills to other settings. The gross motor portion of this project is described including a case study of a deaf-blind youngster who participated in this program. The case study includes a detailed description of the long-term gross motor goals and short-term objectives which were developed for him as part of the project. Progress toward achievement of these objectives is depicted on both a data recording sheet and a graph.

Ria Fuel Behavior Research in the NSRR

Abstract: An in-reactor experimental research on fuel behavior under reactivity initiated accident(RIA) conditions has been progressed in the Nuclear Safety Research Reactor(NSRR). LWR type fuel rods were irradiated by a pulse burst power in the water environment.