Garden Hose Research Articles

Apple Insect Control, Yakima, WA 1982

Abstract Sprays were applied to apple trees using a handgun with pump pressure of 500 lb/in2. All trees were sprayed to runoff, ca. 400 gal/acre. Single tree plots were arranged in a randomized block design and replicated five times. There were 3 applications, 3 Jun., 1 Jul., and on 2 Aug. Trees were irrigated via a drip system. Codling moth and San Jose Scale control was determined by examining 50 fruit per tree at harvest. Leafhopper populations were estimated 5 Jul. by observing the number of adults migrating from a branch when hit with a piece of garden hose.

Cosmic ray north‐south anisotropy: The role of the interplanetary magnetic field

Nucleonic intensity data from the north and south polar stations Thule and McMurdo are analyzed to determine the nature of periodicities in the north‐south asymmetry of relativistic galactic cosmic rays. The 24‐hour average intensity differences on individual days range from 0 to ±1.5%, and the most prominent time variation is a recurrence tendency with a period consistent with the 27‐day solar rotation period. A recently developed procedure for evaluating the statistical significance of quasi‐persistent data has been utilized to establish the reality of the 27‐day signal disclosed by superposed epoch analysis of the north‐south asymmetry data. Analyses of various components of the interplanetary magnetic field reveal that the IMF component (parallel to the nominal garden hose direction) also displays a 27‐day variation with maximum amplitude. Furthermore, a significant relationship between and the north‐south asymmetry is established by Chree analysis. On the basis of this relationship, it is suggested that the 27‐day variation in the north‐south asymmetry arises from the drift, where represents the radial gradient of cosmic rays.

Propagation of hydromagnetic waves through a collisionless, heat-conducting plasma

The propagation of small-amplitude hydromagnetic waves in a collisionless, heat-conducting plasma is investigated using the first-order Chew-Goldberger- Low (CGL) fluid equations including the effect of finite Larmor radius of the ion. The first-order heat flux equations are derived by use of Macmahon's technique. The zeroth-order velocity distribution function of the ion in the CGL expansion is assumed to be a heat-flux-bearing distribution function. The effect of heat flux on the propagation of hydromagnetic waves is analysed by use of phase speed and refractive index surfaces and the amplitude relation between the density perturbation and the magnetic field perturbation. It is shown that the hydromagnetic wave propagation characteristics are asymmetric with respect to the direction of external magnetic field to zeroth order and first order for magneto- acoustic and Alfvén waves, respectively, and the garden hose instability criterion is modified by the heat flux anisotropy.

Cross‐Connection Control in Your Own Backyard

Residential customers may unwittingly cause cross connections when they attach containers of insecticide, herbicide, soapsuds or any other chemical to a garden hose and then connect the other end of the hose to an outside water tap. This article presents examples of residential cross connection and suggests that such incidents may be avoided through use of hose‐bibb backflow preventers.

Garden Hose Cause of Taste Complaint

This article relates an incident in which taste problems were created by a garden hose connected to an outside tap. The remedy for the problem is described, and the importance of good customer relations is emphasized.

Garden Hose Separation of Gaseous Isotopes. Part II: Supersonic Accelerations

A mechanical process for separating gaseous mixtures according to their respective molecular weights, by a variation of the time-of-flight process, is proposed. The separative apparatus consists of several sets of nozzle-deflector combinations surrounded by a stationary collector housed in an evacuated chamber. From a rotating supersonic nozzle, a contiguous plurality of successive groups of molecules is ejected to form a continuous stream of the mixture. The molecules of each group of molecules are allowed to accelerate for a predetermined period of time following their supersonic expansion, thereby allowing each group of molecules to form a generally spherical configuration, the outer radius of which will be enriched in molecules of lighter mass, relative to lesser radii. A deflector means co-rotating with the nozzle is used to deflect molecules that have been allowed to move for the predetermined period of time in accordance with their expansion velocities, from at least one desired portion of the stream, and a stationary collector means is disposed to receive the deflected molecules. The estimated separative work produced from such a unit is about the same or better than that of a modern giant diffuser of similar dimensions. However, with an essentially empty chamber, the unit capitalmore » cost as well as the energy required is competitive with any of the well-known methods, mechanical or otherwise.« less

Generation of irregular (type Pi C) pulsations in the plasma sheet during substorms

The garden hose overstability is shown to be activated in the plasma sheet following an enhanced merging in the magnetotail. The resulting unstable Alfven waves are proposed as a source of the Pi C irregular pulsations that are observed on the ground in close correlation with electron precipitation pulsations during substorms. (AIP)

Making Rainbows with a garden hose

First Page

Garden hose separation of gaseous isotopes

METHODS of separation of isotopes and in particular the separation of uranium isotopes, have long been studied1,2. Here I present a new variation of the “time-of-flight” process, applicable to all gaseous isotopes, although UF6 gas is considered as the example.

Anisotropies in relativistic cosmic rays from the invisible disk of the Sun

The most recent (September 1–2, 1971) of the rare ground level events signaling the arrival at the earth of relativistic solar cosmic rays arising from a flare on the sun's invisible hemisphere displayed marked anisotropy for several hours. Application of newly developed analytical procedures has made it possible to study in detail the evolution of the anisotropic pitch angle distribution. Throughout the anisotropic phase the solar particle flux is proportional to the cosine of the angle between the weighted mean asymptotic direction of viewing and an axis of symmetry corresponding to the spiral interplanetary magnetic field line that connects the sun to the earth. Furthermore, the degree of anisotropy deduced from the ratio of the fluxes in the garden hose direction toward and away from the sun decays exponentially. The results of this analysis and the reexamination of the three previously observed invisible hemisphere ground level events have demonstrated that propagation along the spiral interplanetary field line connecting the sun to the earth occurs even when the source lies far beyond the limb of the sun. In one case (January 28, 1967) the anisotropy near onset was 100% (i.e., no particles traveling toward the sun), a situation that had only been reported twice previously and then in association with visible flares that occurred within 10° of the foot of the nominal garden hose field line. These results bespeak the operation of an efficient transport mechanism in the solar corona that enables relativistic protons to travel over distances at least as great as 70° in heliolongitude in about 15 min.

Pitch angle distribution of solar flare particles in interplanetary space

During the initial anisotropic phase of solar particle events, the flux in the radial direction is considerably less than that from the garden hose field direction. An analysis based on the theory of charged particle transport in random magnetic fields has been conducted to determine the pitch angle distribution of particles with respect to the garden hose field lines. With the commonly observed magnetic field power spectral density functions, the model reveals that the flux is proportional to cos δ, where δ represents the angular separation from the garden hose direction. This theoretical result is verified by the analysis of relativistic solar particle observations during the appropriate anisotropic phases of several otherwise dissimilar ground level events; i.e., those of May 4, 1960; November 12, 1960; November 18, 1968; and February 25, 1969.

�tude hydrodynamique du grand jet coronal ne observ� � l'�clipse du 7 Mars 1970

A Hydrodynamical Study of the Large NE Coronal Streamer Observed during the 7th March Eclipse. The photometry of the large coronal streamer located on the N-E limb of the Sun observed on the 7th March 1970 in Mexico has been performed using compensated plates in unpolarized light as well as in tangentially and radially polarized light. The measured polarizations permit us to locate the streamer in space using a generally used method. The density distribution in the core of the streamer and for r > 1.5 R ⊙ is given as well as the half-widths of the density distribution perpendicular to the axis of the streamer. Densities n(r) in the 1(R ⊙) < r < 1.5(R ⊙) region are obtained assuming hydrostatic equilibrium (4) for 1.5 150(km s−1)] above the height of minimum cross section of the streamer, r = 3.5 (R ⊙). This result is verified by a simple calculation based on the observed curvature of the streamer's ‘stalk’. The velocity corresponding to the garden hose effect considered has a lower value equal to 60(km s−1). The radial distribution of the expansion velocity is shown. Our model allows us to extrapolate in order to obtain the value of v(r) at the Sun's surface. This value, v ≈ 0.07 (km s−1) can be compared with the value of the differential rotation velocity of the ‘foot’ of the streamer. The values of the corpuscular flux of the streamer are calculated [F=2.4 × 1034(ℯ s-1] and agree with the value of the flux corresponding to the density enhancements of the solar ‘wind’, measured in situ. This shows the importance of large streamers for the coronal expansion processus.

A guiding centre Vlasov equation and its application to Alfvén waves

Guiding centre approximations are used to derive the dielectric tensor of a collisionless plasma. This approximate dielectric tensor is used to obtain the dispersion relation of Alfvén waves in a warm plasma. In a ‘low/ β’ equilibrium plasma Alfvén waves are shown to suffer considerable Landau damping if the propagation vector is almost perpendicular to the magnetic field. In a non- equilibrium plasma Alfvén waves can be generated by ‘negative Landau damping’ even if β is low. For sufficiently high β the well-known ‘garden hose’ instability can occur and is then probably dominant. The importance of these two instabilities in the magnetosphere and in the solar wind is discussed.

Anisotropy of Galactic Cosmic Rays and the Interplanetary Magnetic Field

IT has been demonstrated1,2, using data from high counting rate instruments, that the daily variation of secondary cosmic ray intensity measured on the ground can in general be related on each day to an anisotropy of primary galactic cosmic rays. The anisotropy can vary from day to day in magnitude, in the directions with respect to the Earth–Sun line of maximum intensity Tmax and of minimum intensity Tmin outside the influence of the geomagnetic field, and in the energy spectrum of variation. Tmax and Tmin are usually separated by 8–10 h. This has led Rao and Sarabhai to suggest that the anisotropy appears generally to be due to two principal processes, one a modulation equivalent to a pair of oppositely directed positive and negative sources, and the other a negative virtual source approximately oriented along the garden hose direction towards the Sun.

Biology Field Trip: One Foot Away

Biology teachers often feel frustrated at their own inability to arrange appropriate field trips. The nature of the subject matter demands an acquaintance with living forms in their natural habitats. Yet the limitations of the fifty-minute period and the departure of the bus at three-thirty drives many of us to become, more and more, laboratory and textbook teachers. It is in the search to meet this difficult situation that the idea of a field trip-one foot away, has come to me. The one foot applies to an intelligent examination of the soil which may be directly under foot. By way of preparation it can be pointed out that there are two great realms of lifeabove and under ground. We are separated from the latter only by the soles of our shoes, but we see virtually nothing of the dramatic roles played by living things in the subter ranean realm. A preliminary study will remind us that earthworms are drilling holes down there, how or why we are not too sure; ants are nibbling away at the walls of cavities, thereby enlarging them; tiny mites, nematodes, springtails are chewing at the decaying matter of old roots, thereby clearing the channels to become well-travelled highways and more effective drainage ditches; seventeen year cicadas are wandering vaguely about awaiting the expiration of their long sentences before escaping from their underground prisons; rabbits and woodchucks burrow short distances into the dark and mysterious soil. But the real mass of activity is poorly understood. The following studies, observations and experiments were devised to throw more light on this dark region under foot. Latex casts of tunnels. In order to make a cast of the various types of cavities and tunnels made in the soil, liquid latex is excellent (Gamer 1953). It is poured into the soil that has been tunnelled, until the soil will hold no more. It is allowed to congeal for a couple of days and the lump of soil is dug up; the soil particles are washed away with a stream from a garden hose; the latex mold shows clearly the glazed tubes of earthworms, the nibbled cavities of ants, and the irregular voids of shrinkage cracks.

STUDIES ON THE BLOOD VESSELS IN THE MEMBRANES OF CHICK EMBRYOS

On the basis of the anatomical studies presented the following inferences or conclusions are drawn. 1. In the course of development there appear in the vascular membranes of chick embryos arterial vessels of all calibers, namely, capillaries, small arteries with 2 or 3 cell layers, and large arteries formed of endothelium, longitudinal and circular layers of muscle and adventitia. 2. In none of the stages are elastic fibers developed. Only in the most central portion of the umbilical artery, in that portion namely which is to be regarded as belonging to the embryo, are elastic fibers discoverable. 3. The structure of capillaries is histologically the same at all stages. The small arteries of embryos 10 days old resemble histologically those of 18. At no stage of development are appearances of degeneration nor of fat to be found in arteries. When the physiological results of our investigations are compared with the anatomical ones the following comments may be made. In respect to Paragraph 1 of the anatomical results we may remark that when we study the different forms of the wall of arterial vessels the most delicate vessels consisting of single cells exhibit the greatest irritability. Those which are built of 3 to 4 muscle layers are less irritable. Stouter vessels appearing for the first time at 10 days of incubation require stronger stimuli to bring about the same reaction. In respect to Paragraph 2 of the anatomical results we may make this comment. The absence of elastic fibers in all arteries of the embryonic membranes throughout the period of their development is important in defining a physiological property of the larger vessels. The medium and larger vessels, beginning with the 4th day of incubation, contract differently from normal adult human arteries. In the contracted state they appear in cross section not as small replicas of larger circular structures, but take on a new form. During the course of contraction they become flat and appear band-like as would a garden hose when it is compressed by a weight. In examining a vessel so contracted one sees on rotating the vessel either a broad side or a narrow one. It is for this reason that such arteries appear alternately narrow as a line or broad as a band. It is not until the narrow artery is elevated with a hook that its uniform band-like nature becomes evident. The absence of elastic tissue, the presence of which in all probability is mainly responsible for the usual shape of arteries on cross section, permits one to see how the phenomenon which has been described may come about. Concerning Paragraph 3 of the anatomical conclusions we have this to say. According to the histological investigation a stage of degeneration is wanting in the blood vessels of the embryonic membrane in a sense in which one is accustomed to see such changes in other blood vessel systems during the course of life. On the day of hatching the constituent cells and fibers of the arteries of all calibers are anatomically the same as in their early development. These vessels do not die as the result of aging: The nutrient fluid ceases to flow because of contraction of the umbilical vessels. The blood vessels die in complete possession of their physiological irritability and anatomical integrity. The unaltered irritability of blood vessels of the same caliber at all ages is consonant with their unaltered anatomical structure.

The high-voltage potentiometer

The author describes a high voltage potentiometer which may be made at reasonable expense consisting of a water resistance potential distributor and a sparking probe potential difference detector. The water resistance consists of a column of water moving slowly through an ample length of garden hose, and tapping in points through which to connect the probe are provided by breaking the hose at regular intervals and connecting it with any of the plain metal connectors found on the market as “hose menders.” The results of an integrity trial are charted in Fig. 2. The device is intended for investigations in which the results are not required to be known within 2 or 3 per cent of their actual value.

The High-Voltage Potentiometer

The author describes a high-voltage potentiometer which may be made at reasonable expense consisting of a water resistance potential distributor and a sparking probe potential difference detector. The water resistance consists of a column of water moving slowly through an ample length of garden hose, and tapping in points through which to connect the probe are provided by breaking the hose at regular intervals and connecting it with any of the plain metal connectors found on the market as ``hose menders.'' The results of an integrity trial are charted in Fig. 2. The device is intended for investigations in which the results are not required to be known within 2 or 3 per cent of their actual value.