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991.
Two comparison groups of 25 Ss each, Fit and Lack of Fit, were generated based on extent of similarity between their ideal and real perceptions of a rehabilitation center on the Community-Oriented Program Environment Scale (an index of person/environment fit). Although Lack of Fit Ss reported more problems in receiving center services, more dissatisfaction with services, and lower life satisfaction in the present, they were no more likely to drop out of their center program. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
992.
Distortions in received signals in solar occultation measurements made from space arise as a result of the systematic motion of the electro-optical sensor. In a wide range of cases, the motion-related signal distortions caused by the instrument's full modulation transfer function are as important as those from the optics. This paper demonstrates by simulation that existing techniques in the field of digital-image processing can be applied directly to solar occultation experiments to correct for these distortions. The resulting enhanced radiation profile is much closer to the true radiance profile than is the sampled output of the instrument. Use of this enhanced radiance profile in the inversion computation should improve the retrieved atmospheric profiles considerably. It also contains a study of the accuracy of such application from the point of view of instrument noise, uncertainties in the knowledge of the instrument function, and the nature of the power spectrum of the undistorted signal.  相似文献   
993.
A Bose-atom model is introduced for the molecule DH where H represents a heavy halogen atom. A potential is constructed for this system and corresponding wavefunctions and energies are obtained. In the ground state, the large mass of the deuteron causes large penetration into the ion core. An expression for the probability of deuteron-nuclear overlap is obtained of the form P = (1.4rN/a0)2f/4√πf32 where rN is nuclear radius, a0 is Bohr radius, Z is atomic number and f = √2Zmdme ? 1. Thus P is infinitesimally small. Relevance to the exothermic reaction 127I(d,n) 128Xe is discussed.  相似文献   
994.
Investigations of biofilms in domestic environments are sparsely represented in the literature. In this study, samples of various household surfaces, including food, laundry and kitchen items, were analyzed for evidence of biofilm presence. Visualization of the surfaces was carried out using cryostage scanning electron microscopy (CSEM) and light microscopy. Qualitative evidence of the presence of biofilm formation was obtained from all of the sample groups analyzed, suggesting the widespread existence of microorganisms in biofilms on domestic surfaces. This suggests that biofilms may be important in household hygiene, and highlights the need for standardized, approved biofilm methods suitable for consumer products testing.  相似文献   
995.
High winds, flooding, lightning, and other phenomena associated with adverse weather can cause power failures, equipment damage, and process upsets resulting in chemical releases. Of the 5000 events in Texas that were reported to the Hazardous Substances Emergency Events Surveillance (HSEES) system during 2000-2001, adverse weather conditions contributed to 110 (2%) events. Rain was the most frequent adverse weather condition. Most events to which adverse weather conditions contributed occurred during June or September; these months correspond with the high temperature and hurricane season in Texas. Most events occurred in coastal counties with large numbers of industrial facilities. Three industries reported the majority of events: industrial and miscellaneous chemicals manufacturing; petroleum refining; and plastics, synthetics, and resin manufacturing. Power failures were associated more often with adverse weather-related events than with nonweather-related events. Releases occurred most commonly from ancillary process equipment and process vessels. Events associated with adverse weather-related conditions involved nine victims. System and process design improvements, such as improved backup power generation and redesigned secondary containment systems, could be explored to reduce the potential negative effects of severe weather.  相似文献   
996.
The conventional way of determining the flammability characteristics of a material involves a number of tedious single-sample tests to distinguish flammable from non-flammable conditions. A novel test device and fuel configuration has been developed that permits multiple successive tests for indefinite lengths of thin solid materials. In this device, a spreading flame can be established and held at a fixed location in front of optimized diagnostics while continuous variations of test parameters are made. This device is especially well-suited to conducting experiments in space (e.g. aboard the International Space Station) where the limited resources of stowage, volume, and crew time pose major constraints. A prototype version of this device was tested successfully in both a normal gravity laboratory and during low-gravity aircraft trials. As part of this ongoing study of material flammability behavior, a numerical model of concurrent-flow flame spread is used to simulate the flame. Two and three-dimensional steady-state forms of the compressible Navier-Stokes equations with chemical reactions and gas and solid radiation are solved. The model is used to assist in the design of the test apparatus and to interpret the results of microgravity experiments. This paper describes details of the fuel testing device and planned experiment diagnostics. A special fuel, developed to optimize use of the special testing device, is described. Some results of the numerical flame spread model are presented to explain the three-dimensional nature of flames spreading in concurrent flow and to show how the model is used as an experiment design tool.  相似文献   
997.
Two new cation-deficient hexagonal perovskites Ba4NdTiNb3O15 and Ba3Nd2Ti2Nb2O15 were prepared in the BaO–Nd2O3–TiO2–Nb2O5 system by high temperature solid-state reaction route. The phase and structure of the ceramics were characterized by X-ray diffraction and scanning electron microscope (SEM). The microwave dielectric properties of the ceramics were studied using a network analyzer. Ba4NdTiNb3O15 has a dielectric constant of 38.15, a high-quality factors (Q u ×f >18 700 at 5.4422 GHz), and a small temperature coefficient of resonant frequency ( f )+12 ppm °C–1 at room temperature; Ba3Nd2Ti2Nb2O15 has a higher dielectric constant of 46.83 with high-quality factors Q u ×f >19 500 at 5.0980 GHz, and f +28 ppm °C–1.  相似文献   
998.
Sr4La2Ti4M6O30 (M=Nb or Ta) compounds were synthesized by the conventional powder compaction and high temperature solid state reaction technique. The dielectric properties of the sintered samples were measured and they were further characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) methods. Sr4La2Ti4M6O30 compounds are paraelectric phases adopting filled tetragonal tungsten–bronze (TB) structure at room temperature. Sr4La2Ti4Nb6O30 and Sr4La2Ti4Ta6O30 show high dielectric constants of 387 and 166 together with low dielectric loss of 0.0084 and 0.0042 at 1 MHz, respectively.  相似文献   
999.
A new mathematical treatment of alarms that considers them as multi-variable interactions between process variables has provided the first-ever method to calculate values for alarm limits. This has resulted in substantial reductions in false alarms and hence in alarm annunciation rates in field trials. It has also unified alarm management, process control and product quality control into a single mathematical framework so that operations improvement and hence economic benefits are obtained at the same time as increased process safety. Additionally, an algorithm has been developed that advises what changes should be made to Manipulable process variables to clear an alarm. The multi-variable Best Operating Zone at the heart of the method is derived from existing historical data using equation-free methods. It does not require a first-principles process model or an expensive series of process identification experiments. Integral with the method is a new format Process Operator Display that uses only existing variables to fully describe the multi-variable operating space. This combination of features makes it an affordable and maintainable solution for small plants and single items of equipment as well as for the largest plants. In many cases, it also provides the justification for the investments about to be made or already made in process historian systems. Field Trials have been and are being conducted at IneosChlor and Mallinckrodt Chemicals, both in the UK, of the new geometric process control (GPC) method for improving the quality of both process operations and product by providing Process Alarms and Alerts of much high quality than ever before. The paper describes the methods used, including a simple visual method for Alarm Rationalisation that quickly delivers large sets of Consistent Alarm Limits, and the extension to full Alert Management with highlights from the Field Trials to indicate the overall effectiveness of the method in practice.  相似文献   
1000.
Polylactide-co-glycolide (PLGA) foams of tubular shape were assessed for their use as soft-tissue engineering scaffolds in vitro and in vivo. Porous membranes were fabricated by a thermally induced phase separation process of PLGA solutions in dimethylcarbonate. The parameters investigated were the PLGA concentration and the casting volume of solution. Membranes produced from 5 wt/v % polymer solutions and a 6 ml casting volume of polymer solution were selected for fabricating tubes of 3 mm diameter, 20 mm length and a nominal wall thickness of 1.5 mm. Scanning electron microscopy revealed that the structure of the tubular foams consisted of radially oriented and highly interconnected pores with a large size distribution (50-300 microm). Selected tubes were implanted subcutaneously into adult male Lewis rats. Although the lumen of the tubes collapsed within one week of implantation, histological examination of the implanted scaffolds revealed that the foam tubes were well tolerated. Cellular infiltration into the foams, consisting mainly of fibrovascular tissue, was evident after two weeks and complete within eight weeks of implantation. The polymer was still evident in the scaffolds after eight weeks of implantation. The results from this study demonstrate that the PLGA tubular foams may be useful as soft-tissue engineering scaffolds with modification holding promise for the regeneration of tissues requiring a tubular shape scaffold such as intestine.  相似文献   
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