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21.
Airbag injuries have resulted in the deaths of several infants and small children, and such deaths are generally associated with rearward-facing infant seats or unrestrained children in front passenger seats of cars equipped with airbags. An airbag can also cause death in a small child wearing a shoulder/lap belt, however, as this case report illustrates. A two-year-old female was involved in a low-speed collision while riding in the front passenger seat of a dual-airbag-equipped automobile. Secondary impact with the airbag caused catastrophic occipitoatlantoaxial disarticulation with traumatic spinal cord separation, thermal injury and abrasions of the right forearm and distinctive patterned abrasions of the face. The possibility of airbag injury should be considered in all low-speed traffic fatalities, and the confirmatory injuries sought at postmortem examination.  相似文献   
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A numerical analysis of the laminar flow of a Newtonian fluid in the inlet section of a circular pipe has been carried out for a Reynolds number range of 0 to 500, employing a finite element based CFD code. A new flow phenomenon has been identified at low Reynolds numbers (<50), viz, the existence of a peak in the axial pressure profile at a small distance from the entrance. Existing correlations for the entry length are shown to be insufficient and a new correlation for the entry length is proposed.  相似文献   
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近年来,人们对环保和健康要求的提高,给溴系阻燃剂的发展造成了很大影响。虽然欧盟RoHS禁令明确禁用多溴联苯和多溴联苯醚类阻燃剂后,又豁免了十溴联苯醚(DECA),但它的危害性仍然受到人们的普遍质疑。文章对这种卤化阻燃剂的安全使用性进行了讨论。  相似文献   
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Drop‐based crystallization techniques are used to achieve a high degree of control over crystallization conditions in order to grow high‐quality protein crystals for X‐ray diffraction or to produce organic crystals with well‐controlled size distributions. Simultaneous crystal growth and stochastic nucleation makes it difficult to predict the number and size of crystals that will be produced in a drop‐based crystallization process. A mathematical model of crystallization in drops is developed using a Monte Carlo method. The model incorporates key phenomena in drop‐based crystallization, including stochastic primary nucleation and growth rate dispersion (GRD) and can predict distributions of the number of crystals per drop and full crystal size distributions (CSD). Key dimensionless parameters are identified to quickly screen for crystallization conditions that are expected to yield a high fraction of drops containing one crystal and a narrow CSD. Using literature correlations for the solubilities, growth, and nucleation rates of lactose and lysozyme, the model is able to predict the experimentally observed crystallization behavior over a wide range of conditions. Model‐based strategies for use in the design and optimization of a drop‐based crystallization process for producing crystals of well‐controlled CSD are identified. © 2009 American Institute of Chemical Engineers AIChE J, 2010  相似文献   
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An electrothermal-swing adsorption system was demonstrated on the bench scale for capture and recovery of organic vapors from air streams. Methyl propyl ketone (MPK), methyl ethyl ketone, n-hexane, acetone, and methylene chloride were removed and recovered at 200–1,020?ppmv in a 40.0 slpm air stream while using activated carbon fiber cloth (ACFC) adsorbent. Removal efficiencies were greater than 99.9%. Liquid recovery fractions increased with increasing relative pressure, ranging from 0.11 for methylene chloride (P/Psat = 2.1×10?3) to greater than 0.80 for MPK (P/Psat = 2.2×10?2). The electrical energy consumed during regeneration per mol of liquid organic compound recovered decreased with increasing relative pressure of the inlet gas stream, ranging from 4,698 kJ/mol for methylene chloride to 327 kJ/mol for MPK. Equilibrium ACFC adsorption capacity, throughput ratio, and length of unused bed were also evaluated. These results are encouraging for the development of a new technology to capture and readily recover a wide range of organic vapors from air streams.  相似文献   
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Several different types of communication disturbances have been identified in the speech of schizophrenia patients. This study assessed 6 types of referential communication disturbances in the speech of 32 stable outpatients, 23 of their nonschizophrenic siblings, and 27 control subjects. The siblings made more frequent reference failures of all types than control subjects and did not differ from the patients on most types of disturbance. Only on the arguably most "schizophrenic" type of disturbance, the missing information reference, did patients show more deviance than siblings. On the vague reference, siblings showed more deviance than patients. These results, which are very similar to those previously reported on parents of patients, support the idea that referential disturbances reflect vulnerability to schizophrenia. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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A sorbent injection test program was carried out at NRG Texas Power LLC's (NRG) Limestone Electric Generating Station (LMS). LMS fires a 30/70 blend of Powder River Basin (PRB) and Texas Lignite, and is equipped with a cold-side electrostatic precipitator (ESP) and wet scrubber. The plant markets its fly ash for beneficial use, so development of a low ash impact mercury control technology is important to the economics of implementing a mercury control system. In addition to standard activated carbon injection, two different low ash impact mercury control technologies were evaluated in parametric tests: low ash impact sorbents and Toxecon™ II. The parametric ACI test program conducted at LMS demonstrated that high (>90%) levels of mercury removal could be achieved with carbon sorbents. The Toxecon™ II design used at LMS did not provide for as high a mercury removal as injection upstream of the ESP, likely due to poor coverage of the cross-sectional area of the ESP. Limited concrete testing was performed with simulated ash/carbon mixtures. As expected, the amount of air-entraining additive required increased with increasing carbon content in the ash. However, it appeared that small amounts of non-passivated carbon may be acceptable in fly ash for concrete use.  相似文献   
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This study is one of the first to investigate the relationship between low birth weight and cognitive outcomes in an urban, poor, prospectively designed African-American birth cohort. Multivariate analyses of the Pathways to Adulthood study, a subset of the Johns Hopkins Collaborative Perinatal study, compared low birth weight African-American children with normal birth weight African-American children on the Wechsler Intelligence Scale for Children (WISC) at seven years of age. When controlling for various sociodemographic factors, associations were obtained for the very low birth weight group (less than 2000 g) indicating an overall 7 point IQ difference. Milder associations were reported in the moderately low birth weight (MLBW) group (2000 to 2500 g) resulting in a 3 IQ point decrement compared to a normal birth weight reference group. There were no differential effects for gender. Our study revealed a gradient relationship between low birth weight/preterm birth and cognitive ability. Implications for school psychology prevention, assessment, and intervention are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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