bluuebunny/crossref_metadata_2025_split huggingface dataset:
California's Noise Insulation Standards for Multi-Family Residential Construction
Authors: Van Houten JJ 
Published: March 2009

Requirements for noise insulation are included in the design of all new multi-family dwelling units to be constructed in California after August 1974. Noise Insulation Standards are part of the California Administrative Code (Title 25, Section 1092) and are enforced by local building departments throughout the state. The standards apply to all new multi-family dwelling units, such as hotels, apartments, duplexes, townhouses, and condominium units. Detached single-family dwellings are specifically excluded.
The standards establish minimum requirements for the isolation of interior spaces from exterior noise and set minimum ratings for noise insulation of partitions between dwelling units. The community noise equivalent level (CNEL) of 45 dB is set as the maximum for intrusive noise from exterior sources. ASTM testing procedures for party wall and floor/ceiling system sound transmission provide the basis for setting minimum acceptable performance of separations between units.
Based on a study of numerous (over 200) residential projects, it has been found that a certification that the final design complies with the standards is generally required and provided as part of the consulting effort. Field tests are required when the sound transmission performance of the completed structure is questioned by the building official.
The paper provides a brief description of the standards, their enforcement, pitfalls and an assessment of their impact on residential construction in California.
Abatement of Aircraft Noise and Related Regulatory Actions
Authors: Sperry WC 
Published: March 2009

In conformance with the Noise Control Act of 1972, the Environmental Protection Agency (EPA) has proposed to the Federal Aviation Administration (FAA) for promulgation eleven regulations for the control of aircraft noise and is considering several more. The EPA's proposed regulations logically fall into three categories defined by the segment of the aviation community that would be regulated, that is, manufacturers, aircraft operators, and airport operators. Those categories can be interpreted, with some liberties taken to suit the subject (aviation), to represent the source, path, and receiver noise control options which are commonly used in the discipline of acoustics as a technique for subdividing complex noise control problems into managable parts. Also, where noise control capability is highly dependent upon technology, which is always true for source control of aircraft noise, the EPA's proposed regulations are time-phased. That is, the noise requirements are based upon the results of past, present, and future programs of research, development, and demonstration which can be classified in terms of current, available, and future noise control technology.
The concepts of abating aircraft noise by exercising the source, path, and receiver noise control options taken together as a system and by time-phased regulations are described. Regulations proposed by the EPA designed to implement those concepts are presented as examples. Specific regulations which are time-phased in terms of current, available, and future noise control technology are examined in more detail and the economic consequences discussed.
Flaw Criticality of Graphite/Epoxy Structures
Authors: Konishi DY , Lo KH 
Published: March 2009

The orderly assessment of the serviceability of graphite/epoxy structures requires a knowledge of their flaw criticality. In the Serviceability Program, industry-wide flaw likelihood/criticality surveys have been conducted and the results have been qualitatively assessed. These results were used to set nondestructive evaluation (NDE), analytic study, and experimental verification goals. The progress of this program is reported herein.
Flaws, which can result from the fabrication process, normal service utilization, and battle damage have been categorized into five types, depending on their associated stress field disturbance. Flaw detectability studies have been conducted to determine the optimal NDE process to detect these flaws. Analytic studies have been to conducted to determine the disturbance to the stress field in the vicinity of the flaws and to assess their criticality, that is, their structural integrity.
These results were used to define coupons and elements where the elements represent structures that are in a realistic stress state. Accelerated “worst expected” case environmental fatique testing has been conducted. The preliminary results show, as expected, that advanced composites are relatively damage-tolerant. Since further testing is being conducted, an up-to-date status of the program is given.
Three types of coupons are being tested. The tension coupons contain flaws such as holes, delaminations, ply separations, and scratches. The compression coupons contain delaminations, in untapered and tapered regions, and ply separations. The bolted-joint coupons contain notches at bolt holes, oversized holes, and delaminations. Static tests, both room-temperature dry and 82°C (180°F) temperature wet, are being conducted. Spectrum fatigue tests followed by residual strength tests are also being conducted. Both room-temperature dry and realistic temperature/moisture environments are used. Flaw growth specimens are also being tested. The results for the tension flaw screeing specimens are presented and assessed.
Development and Application of the Rolling Contact Fatigue Test Rig
Authors: Bamberger EN , Clark JC 
Published: March 2009

The rolling contact (RC) fatigue test rig was developed specifically for rapid and inexpensive evaluation of materials and processes for rolling element bearing applications. The simple geometry of the test specimen, a cylindrical bar, makes it ideal for evaluating new materials where only limited quantities of the material may initially be available and also permits precise control of the mechanical and thermal processing of the test specimen.
This paper will discuss the development of the RC rig and will detail some of the major investigatory programs which have been performed in the authors' laboratory. This includes the evaluation of metallic and nonmetallic materials for bearing operation, effects of different metallurgical structures on rolling contact fatigue, and the investigation of unique processes such as ausforming and hollow rolling elements. The results of these investigations will show the relevance of the RC rig to full-scale bearing tests and to actual bearing operation in service. Last, the initial work performed on the second-generation RC rig, a high-speed version capable of surface speeds up to 25 m/s (82 ft/s), permitting operation well into the elastohydrodynamic regime, will be briefly reviewed.
Rolling Bearing Life Tests and Scanning Electron Microscopy
Authors: Morrison FR , Yonushonis T , Zielinski J 
Published: March 2009

Traditional techniques for the evaluation of a rolling bearing material or lubricant rely on the accelerated life testing of large lots of bearings. The rating of the bearing performance is then established on the basis of statistical estimates of the experimental Weibull parameters.
Optical evaluation of bearing surfaces has long been used to supplement life data. However, optical examination is limited to evaluating the validity of specific test points. Another surface analysis technique, scanning electron microscopy (SEM), can now be used to augment test data because of the high magnifications and depth of field available. SEM examination of tested surfaces at magnifications up to ×1000 can define alterations in surface morphology produced by wear, fatigue, and corrosive failure modes long before signs would be detectable by optical means or failure would be precipitated. These characteristics can be qualitatively evaluated to supplement collected life data, and comparisons can yield relative evaluations of bearing performance. In this manner, meaningful long-range performance projections can be obtained using small test groups.
An example of the application of this technique for the evaluation of a series of synthetic lubricants and mineral oils is presented in this paper.
Effect of Platelike Carbides Below the Rolling Surface in a Ball-Washer Thrust Rolling Contact Fatigue Tester
Authors: Tsubota K , Koyanagi A 
Published: March 2009

It has been observed that platelike carbides form immediately underneath the rolling track of a specimen subjected to rolling contact fatigue tests on the ball-washer thrust type of tester. These carbides are less likely to form when the carbon concentration of the martensite matrix is low and more likely to present themselves when the carbon content is high.
Carbon is diffused in the matrix by repeated stresses in the specimen during rolling contacts. This carbon is caught by dislocations between oxide inclusions in fields right beneath the rolling track, where the density of such dislocations is high, and it precipitates as carbide.
We have assumed that flakings of the specimen from rolling contact fatigue are attributable to the development and propagation of cracks which originate at the site of the platelike carbides under the rolling track. In order to improve the rolling contact fatigue strength of bearing steel, it is necessary to lower the carbon concentration of the matrix while maintaining the hardness required for the rolling element, and also to reduce and finely disperse oxide inclusions.
Influence of Loading System on Crack Propagation and Arrest Behavior in a Double-Cantilever Beam Specimen
Authors: Fourney WL , Kobayashi T 
Published: March 2009

Design and analysis procedures which include dynamic crack propagation and crack arrest are currently under development in order to assure the safety of such structures as nuclear pressure vessels. This type of design and analysis procedure requires a knowledge of the relationship of stress intensity factor (K) as a function of crack speed (å). The minimum value of stress intensity factor (designated as KIm) on the K versus å relationship is of particular importance because crack arrest will occur if the stress intensity factor falls below this minimum value.
Direct determination of the K versus å relationship and of the value of KIm for pressure vessel grade steels is an extremely difficult and complex task. For this reason methods have been developed to approximate KIm values. One such method was developed by Battelle Columbus Laboratory (BCL) and another by Materials Research Laboratory in Chicago. One difficulty involved in an analysis of dynamic crack propagation and arrest is the interaction of the specimen and loading system, and its effect on crack behavior.
This paper describes a series of experiments conducted to determine the influence of loading system on crack jump length and stress intensity as a function of velocity. Rectangular double-cantilever models made from Homalite 100, a birefringent polymer, were tested with two different wedge loading systems. One system used steel loading pins and aluminum wedge. The second system used both plastic pins and plastic wedge. A Cranz-Schardin high speed camera was used to photograph isochromatic fringe patterns associated with propagating and arrested cracks. Dynamic stress intensity factors were determined from the isochromatic fringe loops using a three-parameter Westergaard stress function.
The high speed photographs also were used to determine crack length as a function of time. From this relationship the crack velocity was determined. The results were compared with the predictions of a one dimensional finite difference computer code written by BCL. The crack jump for the models loaded with the plastic pins and wedge was found to be about twice the crack jump for the models loaded by metal pins and wedge for the same initial pin displacement. The amount of energy stored in pin contact stress was computed and when this additional energy was added to the computer input it was found that the proper crack length as a function of time was predicted by the BCL code.
Review of Corrosion and Dimensional Behavior of Zircaloy under Water Reactor Conditions
Authors: Garzarolli F , Manzel R , Reschke S , Tenckhoff E 
Published: March 2009

The corrosion of Zircaloy in water reactors is dependent on the water chemistry of the primary coolant and the fast neutron flux.
Under standard pressurized water reactor (PWR) coolant conditions with hydrogen overpressure, resulting in a low oxygen content in the primary coolant, the fast neutron flux has no measurable influence on the corrosion rate. Therefore, the in-pile corrosion almost follows the out-of-pile behavior. However, in some cases deviations from this general behavior have been observed. Under oxygenated coolant conditions, typically for boiling water reactors (BWRs), the corrosion is enhanced by the fast neutron flux from the early beginning. Three different types of oxide have been observed.
The dimensional behavior of Zircaloy under irradiation is governed by two processes: creep and growth. Creep is dependent on fast neutron flux and saturates with time. Total growth results from irradiation growth, anisotropic creep, and mechanical interference. Both in-pile creep and growth depend on the amount in recrystallization of the material.
Primary Creep of Zircaloy-2 Under Irradiation
Authors: Fidleris V 
Published: March 2009

Primary in-reactor creep of Zircaloy-2 exhibits approximately linear plots of log(creep strain, ϵ) against log (test time, t) that fit relations of the type ϵ = βtm. For longitudinal specimens of cold-worked Zircaloy-2 at about 570 K, neutron flux of 1 × 1017 n m-2 s-1 (E &gt; 1 MeV) and stresses σ below 310 MPa, the parameters β and m are given by β = (1.5 × 10-5) exp[(1.055 × 10-2)σ] and m = 0.24 + (4.5 × 10-4)σ Increasing the neutron flux from 1 to 3 × 1017 n m-2 s-1 or temperature from 490 to 620 K increases the value of β but has little effect on the time exponent m.
Primary creep of annealed Zircaloy-2 at temperatures between 470 and 570 K shows an abrupt decrease in the time exponent after about 10 h. Irradiation before stressing decreases primary creep strain of annealed and of cold-worked Zircaloy-2 at stresses above 300 MPa, but slightly increases primary creep of cold-worked Zircaloy-2 below about 200 MPa.
Chemical Interaction Between Uranium Oxide and Zircaloy-4 in the Temperature Range Between 900 and 1500°C
Authors: Hofmann P , Politis C 
Published: March 2009

Chemical interactions between the UO2 fuel and the Zircaloy-4 cladding material under power cooling mismatch (PCM) conditions are described. The out-of-pile uranium oxide (U02)/Zircaloy-4 reaction experiments were performed with short Zircaloy-4 tubular specimens filled with U02 pellets at temperatures between 900 and 1500°C under variable U02/Zircaloy-4 contact pressures and under inert gas conditions. The annealing periods varied between 3 and 60 min.
Due to the thermodynamic instability between U02 and Zircaloy, U02 is partially reduced by Zircaloy at the high temperatures investigated. The extent of the UO2/Zircaloy reaction as well as the composition of phases depends decisively on whether a good solid contact between U02 and Zircaloy has been established. If a solid contact exists, a (U-Zr)-alloy rich in uranium and an oxygen stabilized α-Zr(O) phase are formed.
The degree of chemical interaction between U02 and Zircaloy is determined by oxygen diffusion in the Zircaloy and the α-Zr(O)-phase formed. The UO2-Zircaloy reactions obey a parabolic rate law whose temperature dependence is given in the corresponding Arrhenius plot. The formation of oxygen-stabilized °-Zr(O) implies heavy embrittlement of the Zircaloy cladding above 1200°C. Thin oxide layers on the cladding tube inner surface prevent UO2/Zircaloy reactions from taking place below 1100°C. Simulated fission products (cesium, iodine, tellurium) in UO2 exert practically no influence on the extent of the reaction.
A comparison of the out-of-pile test results with those of in-pile experiments exhibits a very good agreement with respect to the phases formed.
Use of the Central Mudminnow (Umbra limi) in the Development and Evaluation of a Sister Chromatid Exchange Test for Detecting Mutagens in Vivo
Authors: Bishop WE , Valentine LC 
Published: March 2009

Genetic toxicology is an area of scientific research which is receiving increasing attention. The increasing number of regulations regarding environmental mutagens and carcinogens has stimulated the development of numerous short-term screening test systems capable of detecting these substances. The sister chromatid exchange (SCE) test has become a popular test method both in vitro and in vivo, particularly because of its high sensitivity and relatively simple methodology. SCEs involve the symmetrical exchange of deoxyribonucleic acid (DNA) segments between homologous chromatids which can be readily visualized in appropriately treated and stained metaphase chromosomes. Though the precise mechanism or mechanisms remain unknown, SCE correlates well with, and may be predictive of, genetic damage.
The experiments reported here were designed to evaluate the use of the central mudminnow (Umbra limi) in an in vivo SCE screening test. The mudminnow's karyotype facilitates its use in the SCE test. Four known mutagens were tested: two direct acting—methyl methanesulfonate (MMS), and N-methyl-N′-nitro-N-nitrosoguanidine (MNNG)—and two indirect acting—cyclophosphamide (CP) and dimethylnitrosamine (DMN). Intraperitoneal injection of each compound produced a dose-dependent increase over control frequencies of SCEs in intestinal metaphase chromosomes. The sensitivity and efficiency of the mudminnow SCE test were confirmed and the results compared with those from other commonly used mutagenesis assays. Application of these procedures to other aquatic organisms having a broader toxicological data base should facilitate the development of a model aquatic system that is useful for studying the potential for genetic damage along with other acute and chronic effects.
High-Hardenability Carburizing Steels for Rock Bits
Authors: Diesburg DE 
Published: March 2009

High stresses experienced in rolling cutter rock bits during the drilling of large-diameter, deep oil wells require steels having extra high levels of hardenability. Nickel-molybdenum steels provide the needed hardenability and are being used successfully in the drilling industry. New EX-grades of steel were evaluated in the carburized condition by means of several laboratory tests and compared to the high-nickel SAE 4800 or SAE 9300 grades. The tests included impact fatigue, high-cycle fatigue, impact fracture stress, and plane-strain fracture toughness. In each test, the excellent performance of EX55 (0.87Mn-0.58Cr-1.85Ni-0.75Mo) was demonstrated.
Several compositional variables of EX55 were evaluated to determine their importance on mechanical properties. The variables included core carbon content as well as alloy modifications of chromium, nickel, and molybdenum. Steels having a core carbon content of 0.14 to 0.17 percent were observed to have more potential for exhibiting high impact fatigue resistance than 0.20 percent carbon steels.
A Shorter Route to Steel Tire Cord
Authors: Cowlishaw FR 
Published: March 2009

Processing of steel to give brass-plated high tensile cord suitable for tire reinforcement is lengthy and involves many processes, each requiring a specialized high capital cost plant and a multiplicity of technologies.
The production route adopted is necessary to provide a high quality product capable of giving trouble-free tire manufacture followed by service in tires without failure attributable to the steel cord.
Examination of the route suggests that some simplifications in the final stages of cord making is possible now that machines capable of aggregating up to four wires simultaneously at the wire drawing stage are available.
Multiple drawn wires (twins, triples, and quads) feeding final cord making machinery can give directly without any intermediate stranding operation 1 × n × 0.x mm combinations (where n = number of wires or filaments, and x = wire or filament diameter) such as 1 × 28 × 0.x mm type cords equivalent to the standard 1 × 4 + 6 × 4 × 0.x mm products.
Indications are that properties and manufacturing costs of cords made in the manner outlined compare favorably with cords made by the normal method.
In cooperation with Dunlop Limited, two such products, 3 × 10 × 0.175 mm replacing 1 × 3 + 5 × 7 × 0.15 + 1 × 0.15 mm and 1 × 14 × 0.175 mm replacing 1 × 3 + 6 × 3 × 0.15 mm, have been used successfully in truck tires for a number of years, confirming that bunch-type cords are capable of functioning and meeting the needs of a reinforcing material in tires.
Texture Control of Zircaloy Tubing During Tube Reduction
Authors: Nagai N , Kakuma T , Fujita K 
Published: March 2009

Seven batches of Zircaloy-2 tubing with widely different textures were processed from tube shells of the same size, by different reduction routes using pilger and 3-roll mills. Based on the texture data of these tubes, the texture control of Zircaloy tubing, the texture gradient across the wall, and the texture change during annealing were studied.
The quantitative relationship between the texture parameter and the newly proposed strain ratio parameter was established using empirical equations in the case of both as-rolled and full-annealed tubing. The deformation texture of Zircaloy-2 tubing was dependent on the tool's curvature and was independent of the dimensions of the mother tubes. The different slopes of texture gradients were observed between the tubing of higher strain ratio and that of lower strain ratio. Also, the different types of the basal pole shift during annealing in the α temperature range were observed in the tested tubes.
Chemical Aspects of Iodine-Induced Stress Corrosion Cracking of Zircaloys
Authors: Cubicciotti D , Jones RL , Syrett BC 
Published: March 2009

The thermodynamics of the zirconium-iodine system are summarized. In the gas phase are four stable species: ZrI4, ZrI3, ZrI2, and ZrI. Their enthalpies of formation and free-energy functions are presented. The only one of those species relevant to stress corrosion cracking (SCC) of zirconium alloys by iodine is the tetraiodide. There are also four solid compounds corresponding approximately in composition to the tetra, tri, di, and monoiodides. Ranges of solid solution composition, enthalpies of formation, and free-energy functions for those phases are given. Thermodynamic information for iodine chemisorbed on zirconium surfaces is also presented. These thermochemical results are used to analyze chemical behavior in situations related to SCC. In particular, reaction of cesium iodide with uranium dioxide in a fuel rod may produce an iodine pressure large enough to result in chemisorbtion of iodine on clean zirconium.
Crack initiation sites in commercial Zircaloy tubing were found to be associated with impurities (iron, aluminum, silicon, and chromium) in the Zircaloy surface in microsurface examination of failures produced in iodine-induced SCC tests. It is suggested that the impurity site may react with iodine to form a locally embrittled region that fails under stress and acts as a crack initiator.