Ni-base superalloys have for decades been studied with regard to environmentally influenced intergranular crack propagation. For high temperature fatigue frequencies andlt;0.1 Hz, it has been shown that an oxygen-rich environment promotes time-dependent crack growth while at andgt;0.1 Hz and/or in inert environments (e.g. vacuum) crack growth is cycle dependent. Oxygen interaction at, or ahead of, the crack tip has been pointed out as the reason for the degraded mechanical properties. While many aspects of this type of crack growth have been previously investigated there is still no consensus about the detailed mechanisms, mainly due to the lack of in-detail investigations of the crack-tip region. less thanbrgreater than less thanbrgreater thanHere, crack tip regions in the Ni-base superalloy Alloy 718 were studied. Specimens were subjected to 90 s hold-times at 550 degrees C and 650 degrees C. Crack growth was arrested before final fracture, allowing cross-sectional analyses of the crack-tip region using scanning electron microscopy (SEM). Detailed studies of the crack-tip region were performed using transmission electron microscopy (TEM) and atom probe tomography (APT). For both APT and TEM samples, site-specific focussed ion beam (FIB) sample preparation was performed in a combined FIB-SEM system. The methodology of accessing and analysing the crack tip region is shown. Initial results on oxidation, oxygen penetration and plastic deformation are shown and discussed.
Reason record crack
The work presented in the thesis primarily focuses on problems that are characteristic for thin layers of concrete exposed to imposed loads. More specific, the work aims at investigating, or rather finding ways to evaluate the efficiency of steel fibres as regards the limitation of crack widths in concrete under restrained conditions. To fulfil the ambitions a test method was developed in which concrete toppings were placed on the upper face of a bottom slab that constituted a stiff foundation. The toppings were then exposed to temperature loads that successively resulted in both the formation of vertical cracks in the concrete as well as horizontal cracks along the interface to the substructure. A total number of eight tests divided into two series were then performed using the proposed technique of testing. At each such occasion two toppings were tested simultaneously, one Plain Concrete (PC) and one Steel Fibre Reinforced Concrete (SFRC) specimen. In this way a comparative evaluation of the influence of steel fibres was facilitated. Results showed that end hooked steel fibres, in amounts of 30 to 60 kg/m3, in most cases reduced the maximum widths of appearing cracks substantially although the reinforcement ratios were not sufficient to get completely crack free structures. It is also clear from the experiments that the effect to some extent was influenced by the properties of the interface in the sense that the fibre contribution seemed to increase as the bond quality became poorer. A series of restrained shrinkage tests were also performed primarily for the sake of verification. Within the frames of this study a total of eight half- scale toppings, four with a depth of 6 cm and four with 12 cm depth, were cast on the surface of an old concrete floor. Both plain and steel fibre reinforced concrete specimens were included in the series. Also, for comparison reasons some conventional steel bar reinforced toppings were produced as well. After an initial curing period of three days the specimens were exposed to one-sided drying that successively resulted in the development of visible cracks. From a crack limiting point of view it was concluded that steel fibres were at least as effective as the steel bar mesh, although it was clear that none of the alternatives were adequate for the purpose of achieving crack-free structures. However, the main reason as to why the effect of reinforcement was not as pronounced as anticipated was believed to be that the bond proved to be insufficient. In particular, considering that the ends of the toppings were fastened to the floor by means of expanding bolts this resulted in a too severe load situation. Regarding the influence of the depth it was shown that cracks appeared at a considerably earlier stage for the thin toppings. At the end of the measuring period the cracks were also considerably wider. This was explained as being a result of the considerably faster rate of desiccation experienced for a thin layer. A simple linear elastic Finite Element analysis was also conducted to verify the effect of the sectional depth in addition to the influence of the concrete creep on the development of stresses in the concrete. Results from this study showed that stresses are substantially reduced due to creep effects. It was further shown that the progress of tensile stresses in the concrete is somewhat slower for a thicker section, mainly due to the slower shrinkage strain development.
The facts or data in the particular case upon which an expert bases an opinion or inference may be those perceived by or made known to the expert at or before the hearing. If of a type reasonably relied upon by experts in the particular field in forming opinions or inferences upon the subject, the facts or data need not be admissible in evidence.
A memorandum, report, record, or data compilation, in any form, of acts, events, conditions, opinions, or diagnoses, made at or near the time by, or from information transmitted by, a person with knowledge, if kept in the course of a regularly conducted business activity, and if it was the regular practice of that business activity to make the memorandum, report, record, or data compilation, all as shown by the testimony of the custodian or other qualified witness, unless the source of information or the method or circumstances of preparation indicate lack of trustworthiness. The term "business" as used in this paragraph includes business, institution, association, profession, occupation, and calling of every kind, whether or not conducted for profit.
In light of this holding, we need not decide whether, as the government urges, a forensic chemist's drug analysis is admissible under the business records exception to the hearsay rule. This contention raises an important issue of first impression in this circuit and one on which other circuits have expressed differing views. Compare United States v. Oates, 560 F.2d 45, 63-84 (2d Cir. 1977) (drug analysis by government chemist held inadmissible hearsay not subject to business records exception) with United States v. Baker, 855 F.2d 1353, 1359-60 (8th Cir. 1988) ("When made on a routine basis, laboratory analyses of controlled substances are admissible as business records under Federal Rule of Evidence 803(6)") (citing United States v. Scholle, 553 F.2d 1109, 1124 & n. 4 (8th Cir. 1977)), cert. denied, 490 U.S. 1069, 109 S. Ct. 2072, 104 L. Ed. 2d 636 (1989), and United States v. Ware, 247 F.2d 698, 699 (7th Cir. 1957) (government chemist's drug analysis, although hearsay, was "admissible as having been made in the regular course of business"). For that reason and because we affirm the district court's judgment on an alternative ground, we decline to address applicability of the business records exception. Cf. Hutchinson v. Stuckey, 952 F.2d 1418, 1422 n. 4 (D.C. Cir. 1992) (declining to address "question of first impression in this circuit" when unnecessary in light of alternative ground for disposition)
Where, through the negligence of the owner of a motor vehicle parked on a public way, oil leaked out of a crack in the crank case onto the way and, after the owner had driven the vehicle away, a pedestrian sustained personal injuries through slipping upon the oil and falling, such injuries were "bodily injuries . . . arising out of the ownership, operation, maintenance, control or use" of the vehicle on the way within the meaning of a policy of compulsory motor vehicle liability insurance issued to the owner; distinguishing Caron v. American Motorists Ins. Co. 277 Mass. 156.
PIERCE, J. This is a suit in equity to enforce the payment of a judgment recovered by the plaintiff against one Sidney Sacks, who was insured under a policy issued by the defendant company. The policy was issued in accordance with 34A, inserted in c. 90 of the General Laws by St. 1925, c. 346, 2, and provided, as appears by a copy in the record, indemnity to the insured "against loss by reason of the liability to pay damages to others for bodily injuries . . . sustained during the term of this policy by any person . . . [with exceptions not here material] arising out of the ownership, operation, maintenance, control
Shortly stated, pertinent agreed facts are as follows: In the late afternoon of July 26, 1932, the defendant Sidney Sacks left his truck parked on a public way in front of his place of business and negligently permitted a quantity of oil to escape from a crack in its crank case. This oil leaked out and ran onto a portion of said public highway adjoining Sacks's premises. Sacks knew of the crack in the crank case during the day of the accident, that it had existed a few days prior thereto, and that oil was leaking therefrom onto the highway. By inference it appears that Sacks drove his truck away sometime before 8:15 p.m., July 26, 1932. As an agreed fact it appears that about 8:15 p.m. the plaintiff, while crossing the highway, in the exercise of due care, slipped and fell, as a result of the oil negligently allowed to accumulate on the street, and suffered personal injuries. The plaintiff brought an action against Sidney Sacks in the Municipal Court of the City of Boston and recovered judgment. The company took no part in the tort action and refused to pay the execution. This suit was brought against the company to reach and apply its obligation more than thirty days after entry of judgment in the action. G. L. (Ter. Ed.) c. 175, 112; c. 214, 3 (10).
Another reason for preferring faxes is many healthcare providers still use paper charts, which is why President Obama is pushing for the move to EHRs in the first place. If a paper record needs to be forwarded from one provider to another or to the same provider working out of multiple locations, the easiest way to get it there is by fax. 2ff7e9595c
Comments