[en] The United States produced 257 million short tons of coal in the first quarter of 1992. This was the second highest quarterly production level ever recorded. US coal exports in January through March of 1992 were 25 million short tons, the highest first quarter since 1982. The leading destinations for US coal exports were Japan, Italy, France, and the Netherlands, together receiving 46 percent of the total. Coal exports for the first quarter of 1992 were valued at $1 billion, based on an average price of $42.28 per short ton. Steam coal exports totaled 10 million short tons, an increase of 34 percent over the level a year earlier. Metallurgical coal exports amounted to 15 million short tons, about the same as a year earlier. US coal consumption for January through March 1992 was 221 million short tons, 2 million short tons more than a year earlier (Table 45). All sectors but the residential and commercial sector reported increased coal consumption

[en] Heretofore, a number of papers reported the detection of high Be-7 concentration in the LDEF. It sounded alarming for space flight in the LDEF orbit, since Be-7 has a half life of 54 days and emits gamma rays of 0.48 MeV which is ionizing radiation. Two concerns are raised: the high concentration of harmful rays to spacecraft crews; and the concentration damage to spacecraft electronic components. A need was established to estimate the dosage of this concentration and compare the value of the allowed limits. As a result, the dosage was calculated of 0.03 rad. When this is compared with the human limit of 25 rads and the susceptibility requirement of 800 rads, the Be-7 amount should not be considered critical. The calculation of Be-7 dosage is detailed

[en] During the preparation of a Josephson junction device, one of the steps for making a base electrode is to deposit a superconducting material on a substrate and to anneal the deposited material to make it a continuous homogeneous polycrystalline grain-like electrode material. Ordinarily, the base electrode and the counter electrode materials are deposited in a vacuum system at a vacuum pressure which is below oneX10^-6 torr to remove all contaminants such as oxygen, oxides of carbon and water vapor. It has been discovered that depositing conventional superconducting base electrode and counter electrode materials in the presence of an inert gas at much high vacuum pressures around 20X10-3 torr produce a superior lead-gold superconductive electrode which is substantially immune to thermal cycling

[en] The use of a video camera for training is not a new idea and is used throughout the country for training in such areas as computers, car repair, music and even in such non-technical areas as fishing. Reviewing a taped simulator training session will aid the student in his job performance regardless of the position he holds in his organization. If the student is to be examined on simulator performance, video will aid in this training in many different ways

[en] The basal sandstone of the Chinle Formation (Upper Triassic) and the Salt Wash Member of the Morrison Formation (Upper Jurassic) in the Kaiparowits Plateau, southcentral Utah, were evaluated in terms of uranium potential. Both surface and subsurface data were utilized. Favorability of the basal Chinle sandstone was based on (1) presence of intermediate-size sandstone-filled channels cut into the Moenkopi; (2) presence of carbonaceous material; (3) an adequate source of uranium; and (4) gamma-ray anomalies from test-hole logs. Favorability of the Salt Wash Member of the Morrison Formation was based on (1) sandstone-mudstone ratios that approach equality, and (2) presence of thick sandstone lenses, carbonaceous material, and halos of light-tan to brown limonite staining. Although the basal Chinle sandstone and the Salt Wash Member of the Morrison contain sizable uranium deposits throughout much of the Colorado Plateau, both units lack characteristics that are favorable for significant uranium deposits in the Kaiparowits Plateau

[en] Uranium potential of Tertiary rocks in the Badger Flats--Elkhorn Thrust area of central Colorado is closely related to a widespread late Eocene erosion surface. Most uranium deposits in the area are in the Eocene Echo Park Alluvium and Oligocene Tallahassee Creek Conglomerate, which were deposited in paleodrainage channels on or above this surface. Arkosic detritus within the channels and overlying tuffaceous sedimentary rocks of the Antero and Florissant Formations of Oligocene age and silicic tuffs within the volcanic units provide abundant sources of uranium that could be concentrated in the channels where carbonaceous debris facilitates a reducing environment. Anomalous soil, water, and stream-sediment samples near the Elkhorn Thrust and in Antero basin overlie buried channels or are offset from them along structural trends; therefore, uranium-bearing ground water may have moved upward from buried uranium deposits along faults. The area covered by rocks younger than the late Eocene erosion surface, specifically the trends of mapped or inferred paleochannels filled with Echo Park Alluvium and Tallahassee Creek Conglomerate, and the Antero Formation are favorable for the occurrence of uranium deposits

[en] There has recently been a renewed interest throughout the world in small nuclear units for generating electricity and for other applications. A report by the World Nuclear Association discussing the advantages of small modular nuclear reactors (SMRs) over traditional nuclear reactor designs, states that ''modern small reactors for power generation are expected to have greater simplicity of design, economy of mass production, and reduced siting costs. Many are also designed for a high level of passive or inherent safety in the event of malfunction.'' Since the inception of nuclear power, the size of reactor units has grown from under 100 MWe to more than 1600 MWe. Today, due partly to the high capital cost of large power reactors and partly to the need to service small electricity grids, there is a move to develop smaller units. These may be built individually or as modules in a larger plant. SMRs are a good fit in markets where anticipated electricity demand is projected to increase incrementally, because SMRs could be built in series as needed. SMRs might be particularly attractive in countries that currently rely on diesel generators for producing electricity. Small reactors could make economic sense because of the high cost of diesel generation compared to the low marginal cost of producing electricity from nuclear energy. (Keeping in mind the initial investment costs and the need to establish a national regulatory program.) Some SMR designs are fabricated in a factory and then delivered to the site. This could be a solution for markets that lack the qualified engineers and skilled craft workers needed to construct large reactors on site. This paper will provide an overview of the types and attributes of SMRs in use or under development worldwide, describe the similarities and important differences between designs, discuss potential applications for SMRs, including baseload electricity generation, electricity generation for remote locations and areas with limited grid capacity, desalination, process heat for industrial applications and district heating, and hydrogen production.(author).

[en] The effect of the discrete stellar nature of the gravitational lens galaxy on the imaging of Q0957+561 is considered. Computer simulations of the images show: 1. The source size of Q0957+561 is probably approx.6 x 10¹⁶ cm in the optical continuum. 2. All three images (the faintest as yet unobserved) will vary by approx.50% on a time scale of 100 yr owing to perturbations by stars in the galaxy. The fluctuations will be somewhat more rapid for the faint B2 image. The effect of very low mass stars in the galaxy halo and cluster is virtually undetectable for the postulated source size of Q0957+561 in the B1 and faint B2 images. One would have to monitor the sources for 200 yr to detect such effects in the A image for stars in the range 0.03--0.1 M/sub sun/. 4. The observed 30% variations in the flux of Q0957+561 are unlikely to be due to perturbations by stars. There should be no trouble decoupling the rapid, correlated time variations among the three images from the slow effects of stars

[en] When a radiation emergency occurs media people will respond. The people in the press are the conduit to the public; they provide information. When there is a major tragedy, people instantly turn to the press. However, reporters are not experts in the field of radiation and they are going to bring a great diversity of backgrounds, technical understanding, perception, and their own fears to any story involving a radiation release. Therefore, when any organization has to deal with the media, an informational structure staffed by knowledgeable people is needed in advance to provide timely and accurate information

[en] Numerical models of star clusters containing a massive black hole are computed for the case of a black hole which grows adiabatically in the cluster center. The growth of the hole is assumed to be at a rate longer than the cluster dynamical time scale but shorter than the relaxation time scale