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Common Aero Vehicles (CAVs) are relatively small‐size, un‐powered, self‐maneuvering vehicles equipped with a variety of weapons and launched from space. One of the major obstacles hampering a full the realization of the CAV concept is a present lack of lightweight, high‐temperature insulation materials which can be used for construction of the CAV’s thermal protection system (TPS). A computational analysis is utilized in the present work to examine the suitability of a carbon‐based, coal‐derived foam for the TPS applications in the CAVs. Toward that end, a model is developed for the high‐temperature effective thermal conductivity of foam‐like materials. In addition, an insulation sizing procedure is devised to determine the minimum insulation thickness needed for thermal protection of the vehicle structure at different sections of a CAV. It is found that the carbon‐based foam material in question can be considered as a suitable TPS insulation material at the leeward side and at selected portions of the windward side of a CAV (specifically the portions which are further away from the vehicle nose).

Pretest predictions have been previously made and reported by the Engineering Mechanics Program of the Reactor Analysis and Safety Division for the response of the one sixth scale reinforced concrete model tested by Sandia National Laboratories in July 1987. A series of axisymmetric models were studied with the two-dimensional computer program TEMP-STRESS. This report describes the comparison between the pretest predictions and the experimental results; a post-test analysis with a precracked concrete model is also compared to the pretest predictions and the experimental results. The post-test analysis is in excellent agreement with the experimental results. Explanations are given for the apparent precracked state of the containment vessel.

This paper describes the adaptation of a finite element program with explicit time integration to a massively parallel SIMD computer, the CONNECTION machine. The adaptation required the development of a new procedure, called an ‘exchange’, which consists of an exchange of nodal forces at each time step to replace the standard gather and assembly. In addition, the data was reconfigured so that all nodal variables associated with an element are stored in a processor along with other element data. The architectural and C * programming language features of the CONNECTION machine are also summarized. Various alternate data structures and associated algorithms for nonlinear finite element analysis are discussed and compared. Results are presented which demonstrate that the CONNECTION machine is capable of outperforming the CRAY X-MP/14 by a factor of about 10.

Analyses of the thermomechanical response of Sandia National Laboratories' 1:6-scale reinforced concrete containment are presented. Three temperature—pressure scenarios are analyzed to complete loss of the pressure integrity. These results are compared to the analysis of pressure alone, to assess the importance of thermal effects.

Picrotoxinin, a convulsant in mammals, was nontoxic when topically applied on whole house flies. When synergized with piperonyl butoxide, the topical LD 50 of picrotoxinin on house flies was 6.50 μg/g or 260 times less toxic on house flies than the synergized insecticide, carbofuran, a carbamate cholinesterase inhibitor. When perfused on the isolated thoracic ganglion of house fly, picrotoxinin was less potent in producing convulsions than carbofuran; however, when assayed on the desheathed thoracic ganglion, picrotoxin was more potent than carbofuran. This suggested a substantial barrier to picrotoxinin preventing diffusion into the house fly central nervous system. Of several picrotoxinin analogs synthesized the 2-iodo,4-isopropyl, 6-methylenebromidecyclohexane-γ-lactone was the most potent convulsant.

A coupled model for the analysis of three-dimensional structures interacting with a three-dimensional axisymmetric fluid has been developed. The model is intended for the study of the role of above core structures in core disruptive accidents. Because the fluid model must be capable of interacting with the structure while it experiences large deformations, an Arbitrary Lagrangian-Eulerian (ALE) mesh description, which enables the motion of the nodes to be programmed by the user, was chosen. Both the structural and the fluid model are programmed in a finite element format for the sake of versatility. Example calculations for a two-dimensional bubble problem, which served primarily to verify the computational algorithm for the fluid are presented. For the purpose of examining the capability of the method and simulating the response of above core structures in a CDA, numerous simulations were made of some SRI scale model tests. The results show reasonable agreement with the experiment.

A quasi-Eulerian finite element formulation for the analysis of transients in a fluid with a pressurized bubble is developed in both two and three dimensions. In these methods the mesh can be programmed to move independent of the material, so that the method lends itself well to the treatment of fluid-structure problems. Time integration is performed by an explicit method, and one point quadrature is used in the fluid elements. To eliminate hourglass modes, an hourglass control which is orthogonal to straining and rigid body modes is used. Several examples are described.

Two-dimensional finite element models for the treatment of the nonlinear, transient response of fluids and structures are described. The fluid description is quasi-Eulerian, so that the mesh can move independently of the material and it includes a new finite element upwinding scheme. The structural description is based on a corotational formulation in which the coordinate system is embedded in the elements, and which is applicable to arbitrarily large rotations. The interface between the fluid and structure permits relative sliding, but because of the quasi-Eulerian fluid description the nodes of the fluid and structure can be allowed to remain contiguous. Modelling procedures for treating the various aspects of subassemblies, such as the narrow fluid channels, the fuel bundles which are immersed in the coolant, and the axial flow, are developed. Calculations are made for a symmetric seven-subassembly cluster and compared to experimental results. In addition, the application to a 19-subassembly cluster is described.

The WHAMS-2D and WHAMS-3D codes were used to analyze the dynamic response of the RAS/TREAT shielded shipping cask subjected to transient leadings for the purpose of assessing potential damage to the various components that comprise the cask. The paper describes how these codes can be used to provide an intermediate level of detail between full three dimensional finite element calculations and hand calculations which are cost effective for design purposes. Three free drops were addressed: (1) a thirty foot axialdrop on either end; (2) a thirty foot oblique angle drop with cask having several different orientations from the vertical with impact on the cask corner; and (3) a thirty foot side drop with simultaneous impact on the lifting trunnion and the bottom end. Results are presented for two models of the side and oblique angle drops; one model includes only the mass of the lapped sleeves of depleted uranium (DU) while the other includes the mass and stiffness of the DU. The results of the end drop aalyses are given for models with and without imperfections in the cask. Comparison of the analyses to hand calculations and simplified analyses are given.

Pretest predictions were made by the Reactor Analysis and Safety Division of Argonne National Laboratory for the response of the 1 :6-scale reinforced concrete model to be tested by Sandia National Laboratories. For this purpose a series of axisymmetric models were studied with the two-dimensional computer program TEMP-STRESS and a three-dimensional circumferential segment model with the program NEPTUNE. The two-dimensional models predicted failure at 175–190 psig (1.207–1.310 MPa). However, two different failure mechanisms were indicated: (1) hoop failure of the vessel at midheight following failure of a splice in this area, (2) failure of a weld in the liner near the basemat due to excessive strains. The three-dimensional model predicted failure at an internal pressure of 180–185 psig (1.241–1.276 MPa) by failure of the splices of the hoop rebars just above cylinder midheight in a region away from the equipment hatch opening.

The development of computational techniques and computer codes for the analysis of coupled fluid-structure behavior in the field of breeder reactor safety analysis is described. Methods for linear fluid-structure analysis, which are limited to acoustic or small-displacement, incompressible fluids are summarized first. Nonlinear methods have been found necessary for many of the breeder reactor safety problems because large displacements and nonlinear material behavior are encountered. Two problem classes are considered in detail: hypothetical core disruptive accidents, or containment analysis; subassembly analysis. The evolution of codes for these problems is described along with current capabilities and difficulties, and requirements for future developments.

The STRAW code was developed for the analysis of core components subjected to high-pressure transients. It is a finite element code that models both the fluid and structures. The code is able to tr...

The need to understand concrete behavior under high temperatures in the nuclear industry has become rather acute. Previously, concrete has been used in nuclear industry as inexpensive material for construction and also for radiation shielding. Presently, we are concerned with the structural integrity of the containment, subject to accidental exposure of concrete to excessively high temperatures and chemical attack. Consequently, we are now seeking basic understanding of concrete behavior at extreme environmental condition. Indispensible in mathematical modeling of concrete behavior is the constitutive relation. A constitutive model developed by Takahashi [1] has been incorporated into the coupled thermal-stress analysis code, TEMP-STRESS, which gives the stress-strain relation up to the point of cracking. This paper describes the modeling of cracking behavior. Four crack propagation criteria: the J-integral, the energy release rate, the effective strength and the failure surface criterion are examined. Several numerical examples are given. Situations under which one method might be more convenient to use than the others are discussed.

The implementation of reinforced flexural elements into the thermal-mechanical finite element program TEMP-STRESS is described. With explicit temporal integration and dynamic relaxation capabilities in the program, the flexural elements provide an efficient method for the treatment of reinforced structures subjected to transient and static loads. The capability of the computer program is illustrated by the solution of several examples: the simulation of a reinforced concrete beam; simulations of a reinforced concrete containment shell which is subjected to internal pressurization, thermal gradients through the walls, and transient pressure loads. The results of this analysis are relevant in the structural design/safety evaluations of typical reactor containment structures.

House flies examined the day after receiving sublethal doses of lindane or carbofuran showed a statistically significant decline in their responses to behavioral tests designed to measure flight, locomotion, optomotor activity, and phototaxis. Flies were designated “functional,” “flightless,” or “nontestable” on the basis of their behavioral test responses. Histological examination of their thoracic ganglia revealed holes in the neuropile, termed “vacuoles,” but no “vacuoles” were evident in the ganglia of control flies. There was a statistically significant correlation between the density of “vacuoles” in the thoracic ganglia of lindane-treated flies and their phototactic responses and climbing performance. This correlation was not demonstrated for the carbofuran-treated group. They were less responsive to behavior tests than the lindane-treated group and had more “vacuoles” in their thoracic ganglia. Flight functions were evidently most susceptible to poisoning; some flies were “flightless” but appeared to have normal locomotor functions with few, if any, “vacuoles” evident in the ventral neuropile of their thoracic ganglia. “Vacuoles” were always present in the dorsal or central regions of the mesothoracic neuromeres of “flightless” flies. Flies with disabled legs always had “vacuoles” in the ventral neuropile or their ganglia. Heartbeat recorded the day after poisoning with lindane or carbofuran was usually irregular in amplitude and rate, suggesting that motor innervation from the central nervous system remained functional. Flight motor activity was depressed the day after poisoning in comparison to that recorded from untreated flies.

As preliminary probes to determine the mode of delayed toxic action of O,O,S-trimethyl phosphorothioate (I) in the rat, the effect of I on rat tissue and organs, and on blood, urine, and pharmacokinetic parameters was investigated. Following oral administration, 30 to 200 mg/kg I caused liver necrosis as a major pathological effect. Morphological changes were also observed in the heart, adrenal, tissues of the small intestine, and kidney. Most animals treated with I developed bronchopneumonia after 3 days. Blood samples taken from rats poisoned with 60 mg/kg I showed severe hemoconcentration; however, serum Na+, Cl−, albumin, and total carbonate/bicarbonate varied only slightly. Na+ and Cl− concentrations in the urine showed a steady decline with time following poisoning but K+ levels remained relatively constant. Pharmacokinetic studies showed that 14C levels in the blood following intraperitoneal or intravenous administration of 60 mg/kg [CH3O14C]I were not affected when the animals were cotreated with 5% of the antagonist O,O,O-trimethyl phosphorothioate. However, lower levels of 14C were found in antagonized animals following oral administration.

The kinetics of accumulation and elimination of lethal doses of [ 14 C]carbofuran in the hemolymph of the house fly suggest a one-compartment open model. Carbofuran in the hemolymph appeared to be in equilibrium with that in the tissues very soon after treatment. Following topical application of carbofuran, the rate of onset of symptoms of poisoning was correlated with the amount of carbofuran in the hemolymph, and the onset of convulsions only occurred after the concentration of carbofuran in the hemolymph reached μ M levels. This value correlated well with neurobioassays of known concentrations of carbofuran perfused in saline onto the isolated thoracic ganglion. Following topical doses, carbofuran concentration in the hemolymph reached a peak within an hour and then gradually declined. At an LD 60 dose, the initial decline in carbofuran concentration in the hemolymph over time was significantly slower than the decline after an LD 10 dose, suggesting saturation kinetics. Hemolymph was collected from house flies for up to 3 hr following topical application of toxic amounts of carbofuran. Thereafter, hemolymph volume decreased and blood samples could not be collected. Curiously, hemolymph samples could be collected for 5 hr from house flies that were injected with toxic doses of carbofuran.

Computer program development and modeling procedures for above-core structures (ACS) have recently focused on modeling the buckling and post-buckling behavior of the ACS support columns. These developments are directed toward two considerations: (1) the prediction of the forces exerted by the column in a hypothetical core-disruptive accident (HCDA) in order that the motion of the ACS can be predicted in a coupled fluid-structure analysis, (2) the calculation of the strains and deformations of the support columns so that situations which lead to complete failure can be identified. One of the aims of this study was to examine the effect of the change in cross section, previously not treated, on the behavior of the support columns. For this purpose, models have been developed in which the portions of the column which undergo significant changes in cross section are modeled by plate elements. Results are presented for two sets of studies. In the first set, results are presented for a series of Stanford Research International scale model tests. Comparison of the tests with the computed results shows reasonable agreement. In the second, the column was displaced with a constant velocity at one end to examine its resistance as a function of displacement. The behavior of support columns consisting of two concentric cylinders has also been studied. The interesting feature of this design is that when one of the cylinders buckles, it moves laterally against the other, which may not have buckled. An effective but simple model was developed for representing the interaction between the columns. Results are presented for an HCDA corresponding to a release of 1000 MJ.

This paper describes the formulation of a finite-element procedure for the thermal stress analysis of thin wall reactor components. A general temperature-dependent constituent relationship is derived from a Gibbs potential function and a temperature-dependent yield surface. This form of constitutive relationship is applicable to problems of small strain. A similar form of a hypoelastic-plastic type is also developed for large strains. The variation of the yield surface with temperature is based upon a temperature-dependent, work-hardening model. The model uses a temperature-equivalent stress-plastic strain diagram which is generated from isothermal unaxial stress-strain data. The above constitutive relationships are incorporated into two computer codes and a previously developed numerical algorithm is used with minor modifications. A set of problems is presented validating the thermal analysis capability of the computer codes to a variety of problem types.

A program for predicting the behavior of the hexagonal fuel assembly duct when subjected to internally generated pressures in the LMFBR is described. To a large extent, studies have been made with two-dimensional models of the hexcan. In these problems, the loadings must be restricted to line loads of sufficient length so that axial effects can be neglected. The finite element models range from a single hexcan to models which include both the loaded hexcan, two adjacent rows of hexcans, the coolant layers between hexcans, and the fuel rod assemblies. A nonlinear, transient finite element program called STRAW is used for the analyses. The program accounts for both geometric and material nonlinearities, and has special features for treating the coolant layer between hexcans by a quasi-Eulerian description and vertical flow in the hexcans and layer so that motions of the coolant can be accurately analyzed. The model has been used with loadings ranging from 500 psi to the kilobar range, and has yielded significant results on damage in adjacent assemblies and the restraining effects of the coolant. For example, preliminary results have shown that deformations of the loaded hexcan are reduced by 25 to 50% when the role of the coolant is included and that corner ductility has very large effects on hexcan response.

A reliable and simple method for the routine analysis of pharmaceutical dosage forms by high-performance liquid chromatography using a C18 Bondapak reversed-phase column with a binary solvent system consisting of acetonitrile and 0.05 M potassium dihydrogen phosphate has been developed. Standardised extraction procedures for drugs in various dosage forms have been developed and successfully applied to a wide range of current pharmaceutical formulations.

Abrupt thermal fluxes on the first walls of fusion reactors represent a loading environment that requires advanced analytical capabilities. Solutions are needed to a wide range of postulated conditions to provide guidance for safety features and design modifications. A brief outline is given of a computer code that provides an integrated procedure for handling thermal stresses and large deformations under dynamic conditions. The code includes a new thermoviscoplastic constitutive equation that incorporates thermal softening, failure and strain rate. Solutions to several verification and illustrative problems are given.

A quasi-Eulerian formulation is developed for fluid-structure interaction analysis in which the fluid nodes are allowed to move independent of the material thus facilitating the treatment of problems with large structural motions. The governing equations are presented in general form and then specialized to two-dimensional plane and axisymmetric geometries. These elements have been incorporated in a general purpose transient finite element program and results are presented for two problems and compared to experimental results.

A simple triangular shell element which incorporates the effects of coupling between membrane and flexural behaviour and avoids membrane locking is described. The element uses a discrete Kirchhoff bending formulation and a constant strain membrane element. For the purpose of permitting inextensional modes and thus avoiding membrane locking, a decomposition technique, which can also be viewed as a strain projection method, is used. The method is illustrated first for a beam element and then for a triangular shell element. Results are presented for a variety of linear static problems to illustrate its accuracy and some highly non‐linear problems to indicate its applicability to collapse analysis.

Four N,N′-thiodicarbamate derivatives of carbofuran induced uncoupled convulsions with similar latencies following topical application to the cuticle of tethered SNAIDM house flies, despite considerable differences in their lipophilic properties. There was a small but statistically significant delay in the latency to response to the derivatives compared to carbofuran, but when perfused directly on the exposed thoracic ganglia to assess intrinsic activity, carbofuran acted up to 4.4 times faster than the derivative. It is suggested that the NS bond of the derivatives is cleaved soon after application to the house fly cuticle and carbofuran is released from each derivative in sufficient quantities to accumulate toxic concentrations in the central nervous system at similar rates.

An high-performance liquid chromatographic assay for quinidine and dihydroquinidine sulphates in pharmaceutical dosage forms has been developed. The method makes use of a reversed-phase system with a C18 bonded column and theophylline as an internal standard. Recovery of both compounds is quantitative and the method compares favourably with that of the United States Pharmacopoeia with regard to speed and precision. The method should also be suitable for the control of quinine salts in pharmaceuticals.

Field and laboratory experiments were conducted over a 3-yr period to evaluate the persistence of several dinitroaniline herbicides. Incorporation of these herbicides was delayed for 1, 3, and 7 days after application. Herbicidal activity was assessed by a sorghum bioassay, and by GLC analysis of soil samples. Herbicides least affected by a 2-day delay in incorporation were oryzalin (3,5-dinitro-N4,N4-dipropylsulfanilamide, nitralin 4-(methylsulfonyl)-2,6-dinitro-N,N-dipropylaniline, butralin 4-(1,1-dimethylethyl)-N-(1-methylpropyl)-2,6-dinitrobenzenamine, dinitramine (N4,N4-diethyl-α,α,α-trifluoro-3,5-dinitrotoluene-2,4-diamine), fluchloralinN-(2-chloroethyl)-2,6-dinitro-N-propyl-4-(trifluoromethyl)aniline, and penoxalinN-(1-ethylpropyl)-3,4-dimethyl-2,6-dinitrobenzenamine. Of the herbicides evaluated, trifluralin (α,α,α-trifluoro-2,6-dinitro-N,N-dipropyl-P-toluidine) and profluralinN-(cyclopropylmethyl)-α,α,α-trifluoro-2,6-dinitro-N-propyl-p-toluidine, were the least persistent after a 1-day incorporation delay. Losses of nitralin, butralin, dinitramine, fluchloralin, penoxalin, trifluralin, profluralin, benefin (N-butyl-N-ethyl-α,α,α-trifluoro-2,6-dinitro-p-toluidine), and isopropalin (2,6-dinitro-N, N-dipropylcumidine) increased dramatically when incorporation was delayed 3 or more days. Persistence on the soil fur-face under field conditions was demonstrated the most by oryzalin. After incorporation, dinitramine was least persistent. The effects of temperature in UV light and dark on loss of dinitroaniline herbicides were demonstrated in the laboratory by applying the herbicide to TLC plates of soil. While herbicide losses did occur in 24 h of UV light, differences in herbicide losses were not significantly different between butralin, penoxalin, profluralin, trifluralin, isopropalin, oryzalin, nitralin, fluchloralin, and benefin. Dinitramine was most affected by the UV light. Butralin, oryzalin, nitralin, isopropalin, and dinitramine were least affected by 45 C in the dark with losses of 2 to 10% in 24 h. Profluralin, benefin, and trifluralin were found most volatile with losses of 35%, 25%, and 18%, in 24 h respectively. With increasing moisture levels, no significant increased losses were detected for butralin, nitralin, oryzalin, penoxalin, and isopropalin at the greater moisture contents. There was a moderate increase in the loss of dinitramine with increased soil moisture. AT 33% initial soil moisture, fluchloralin, benefin, and trifluralin were rapidly lost (75 to 94% in 24 h at 30 C). The trifluoro-methyl group was a common structural component where moisture affected the compound's loss. Application of the intermediate to very volatile dinitroanilines to moist soil surfaces without soil incorporation as soon as possible is not feasible unless higher rates of herbicide are applied.

The pressure coefficient dE/dP appears to be sensitive to the ZnS lattice symmetry for the SA donor-acceptor pair, but not for the Mn2+ centres emission. The HP variation of the relative intensities for the SA and Mn emissions suggests a resonant transfer between these centres. The classical Dexter's formula for Pdd does not explain the results for the cubic crystal, whereas the preferential transfer from the SA centers to the 4E(4G) level in Mn2+ follows all reported observations.

The attenuation of pressure waves by the subassembly walls in a reactor core was studied by a two dimensional, finite element program. For these purposes, a hydro-dynamic finite element was incorporated in an existing dynamic structural program. The resulting program has the advantage that complex boundary conditions and the interaction of structural and fluid elements are handled in a straightforward manner. The program was used to model a section of the hexcan and the surrounding fluid; the hexcan was modelled by beam elements. It is shown that the hexcan walls attenuate pressure peaks by about 33 percent in the adjacent subassembly. Thus the subassembly walls may play an important role in confining the effects of local accidents.

A finite element structural model is developed for the upper internals which is capable of treating material nonlinearities and geometric nonlinearities arising from large displacements when subjected to dynamic loads. This structural model can be used either by itself or in an interactive mode with a hydrodynamics code. The upper internal structures which are located above the core and below the head cover may play a significant role in the hydrodynamics of an energy excursion by mitigating its response. The upper internal structure (UIS) is essentially a massive, perforated rigid body which is connected to the reactor head by support columns with a cylindrical cross section. The major response of interest is the buckling of these support columns which results from the compressive forces they sustain when the upper internals are loaded vertically upward by dynamic loads. In addition to buckling, these columns sustain plastic deformations and changes in cross section making geometric and material nonlinearities accountable. For the case of substantial change in the shape of the column cross section, it will be more convenient to treat the behaviour of the elements stiffness in terms of moment-curvature relations which account for the changes in flexural rigidity with change in cross section. Two factors considered of importance in developing the model are: (1) whether an imperfection is necessary in the initial mesh of the columns to trigger buckling and to what extent does the magnitude of the imperfection effect the results; (2) whether the buckling pattern is symmetric or asymmetric. It was established by these studies that elastic buckling is not affected by the magnitude of the imperfection; for plastic buckling, the results are more sensitive to the magnitude. The studies also showed that the UIS mass is sufficiently large so that it cannot be laterally displaced. By checking the deformed shape, it was observed that the column always attempts to reach the symmetric buckling mode. Even if the asymmetric shape is triggered, it is always at a load higher than that required to trigger a symmetric response. The behavior of the model has also been compared with the SRI tests simulating highly energetic CDAs. The model predicts the magnitude of the axial deflection quite well.

Three-dimensional finite element models of a fast breeder reactor’s above-core structures have been incorporated in a finite element program SAFE/RAS (Safety Analysis by Finite Elements/Reactor Ana...

A triangular element which requires only one quadrature point per element is described along with its implementation in the nonlinear, explicit time integration program SAFE/RAS. The implementation of an Ilyushin flow law which eliminates the need for integration through the thickness and simple formulas for stable time steps is also described. The performance of the triangular and quadrilateral elements is compared in large deflection, elastic-plastic problems. Applications to the analysis of above-core structures in breeder reactors are also described.

A method is presented for the safety analysis of reactor containment structures by means of finite elements. The finite element equations of both fluid and structural elements for arbitrarily large, non-linear response are developed and the way in which they are combined is indicated. Both explicit and implicit integration of the equations in time is considered. Three examples of the application of these methods to the analyses of reactor safety problems are described.

High-performance liquid chromatographic (HPLC) methods for the analysis of hydrocortisone containing ointments and creams have been investigated. A method which uses a silica column and involves a minimum of sample pre-treatment has been shown to compare favourably with the triphenyltetrazolium chloride method of the British Pharmacopoeia. For hydrocortisone ointments the HPLC procedure provides results of equivalent precision and has advantages with respect to the time taken for each analysis and specificity. Application of the method to the analysis of hydrocortisone creams has been explored and the deviation between the HPLC and colorimetric method requires further investigation.

The average heartbeat rate of female adult Musca domestica was near 250 beats/min in vivo at 23°C. However, standard deviation values ranged from ±35 to ±60 depending on the individual house fly. Heartbeat rates in tethered house flies fluctuated between cessation to over 300 beats/min. The heartbeat rate was temperature dependent with a Q10 of 2.3. Either a bite by the Lynx spider, Peucetia vividans (Hentz), or severing the abdomen from the thorax caused the heartbeat to become extremely steady at near 300 beats/min which gradually decreased over several minutes. Application of lethal doses of Monitor or Lindane to the house fly caused thoracic temperature to increase by at most 3°C in conjunction with increased convulsive activity and increased average heartbeat rate. In late stages of poisoning, the heartbeat was relatively uniform indicating a disruption in cardioregulatory nervous activity. Response of the house fly to carbofuran or its N-thiomethyl analog was similar to that of Monitor and Lindane except in late stages of poisoning where the heartbeat continued to exhibit large variations in average rate.

The capital invested in electricity supply during the 10-year period 1921–22 to 1930–31 is allocated as between generation and distribution, showing how the latter is becoming the more important side of the industry.The revenue derived from sales of electricity during the same period is also reviewed and allocated as between generation and distribution expenses, showing that although the efficiency of generation has increased materially, there has been little, if any, improvement in distribution efficiency. The causes of this lack of improvement are analysed andsuggestions are put forward for the co-ordinated control of distribution in order to effect improvements and economies.

Muscle potentials recorded extracellularly from one pair of fibers of the dorsal longitudinal flight muscle in the housefly, Musca domestica L., show a very regular pattern with both pairs driven in alternating sequence. Houseflies with chronically implanted electrodes activated the flight muscles without externally observed motion, either walking or in flight, in apparent shivering responses. The frequency of activation of the flight muscle in shivering was temperature dependent below 25°C with Q10 of 2.57. No shiver was recorded above 26°C. During insecticide poisoning, both gross locomotory activity and flight muscle activation first increased, then decreased slightly, then gradually increased again to a condition of tetany. After treatment with lethal doses of peripheral nerve poisons such as DDT, and pyrethrin analogs, the flight muscle activity pattern gradually increased in tetany and was constantly active for several hours. When poisoned with central nervous poisons such as lindane, dieldrin, endrin, and organophosphorus and carbamate anticholinesterase poisons, the post-tetanic period of poisoning was characterized by discrete bursts of motor unit activation interrupted by inactivity. The high-frequency spasms of flight muscle activity during poisoning resembled hyperactivity obtained due to overheating of houseflies.

The accumulation of 14 C-labeled carbofuran, leptophos, and Monitor ® into the thoracic ganglion of the housefly, Musca domestica , was measured following topical application on the abdomen or perfusion of the ganglion by the compounds in saline solution. The penetration of 14 C insecticide into the thoracic ganglion was corelated with a disruption in characteristic coupling between units of the flight motor, termed uncoupling. An accumulation of about 25 pg of carbofuran per thoracic ganglion was correlated with uncoupling, while leptophos or monitor did not produce uncoupling until 1000 pg had accumulated in the thoracic ganglion. It was noted that carbamate insecticides are generally fast acting as a class compared to organophosphorus insecticides whether treated topically on the whole housefly or perfused directly on the isolated thoracic ganglion. It was concluded that this general property was due to an inherent difference in the interaction of these classes of insecticide with the central nervous system.

Two-dimensional finite-element models for the treatment of the nonlinear, transient response of fluids and structures are described. The fluid description is quasi-Eulerian, so that the mesh can move independently of the material, and it includes a new finite-element up-winding scheme. The structural description is based on a co-rotational formulation in which the coordinate system is embedded in the elements, which is applicable to arbitrarily large rotations. The interface between the fluid and structure permits relative sliding, but because of the description of the quasi-Eulerian fluid, the nodes of the fluid and structure can be allowed to remain contiguous. Modeling procedures for treating the various aspects of subassemblies, such as the narrow fluid channels, the fuel bundles which are immersed in the coolant, and the axial flow are developed. Calculations are made for a symmetric 7-subassembly cluster and compared to experimental results. In addition, the application to a 19-subassembly cluster is described.

Three-dimensional finite-element models for the treatment of the nonlinear, transient response of a fast breeder reactor's above-core structures are described. For purposes of treating arbitrarily large rotations, node orientations are described by unit vectors and the deformable elements are treated by a corotational formulation in which the coordinate system is embedded in the elements. Deformable elements may be connected either to nodes directly or through rigid bodies. The time integration is carried out by the Newmark ..beta.. method. These features have been incorporated to form the finite-element program SAFE/RAS (Safety Analysis by Finite Elements/Reactor Analysis and Safety Division). Computations are presented for semianalytical comparisons, simple scoping studies, and Stanford Research Institute (SRI) test comparisons.

Taste preferences in young pigs have been examined using both long term and short term two choice preference tests. The substances used were examined over a wide range of concentrations; they included sucrose, glucose, sodium saccharin and sodium cyclamate. Relative to water the pigs had a very strong preference for solutions of sucrose and glucose and a strong preference for saccharin. They displayed no preference for solutions of sodium cyclamate. Using operant conditioning methods it was possible to demonstrate that the pigs would learn to perform operant responses in order to obtain sucrose solutions and their motivation to respond on progressive ratio schedules of reinforcement was related to the concentration of sucrose which they obtained.