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51.
Objective: This study compared biomechanical responses of a normally seated Hybrid III dummy on conventional and all belts to seat (ABTS) seats in 40.2 km/h (25 mph) rear sled tests. It determined the difference in performance with modern (≥2000 MY) seats compared to older (<2000 MY) seats and ABTS seats.

Methods: The seats were fixed in a sled buck subjected to a 40.2 km/h (25 mph) rear sled test. The pulse was a 15 g double-peak acceleration with 150 ms duration. The 50th percentile Hybrid III was lap–shoulder belted in the FMVSS 208 design position. The testing included 11 <2000 MY, 8 ≥2000 MY, and 7 ABTS seats. The dummy was fully instrumented, including head accelerations, upper and lower neck 6-axis load cells, chest acceleration, thoracic and lumbar spine load cells, and pelvis accelerations. The peak responses were normalized by injury assessment reference values (IARVs) to assess injury risks. Statistical analysis was conducted using Student's t test. High-speed video documented occupant kinematics.

Results: Biomechanical responses were lower with modern (≥2000 MY) seats than older (<2000 MY) designs. The lower neck extension moment was 32.5 ± 9.7% of IARV in modern seats compared to 62.8 ± 31.6% in older seats (P =.01). Overall, there was a 34% reduction in the comparable biomechanical responses with modern seats. Biomechanical responses were lower with modern seats than ABTS seats. The lower neck extension moment was 41.4 ± 7.8% with all MY ABTS seats compared to 32.5 ± 9.7% in modern seats (P =.07). Overall, the ABTS seats had 13% higher biomechanical responses than the modern seats.

Conclusions: Modern (≥2000 MY) design seats have lower biomechanical responses in 40.2 km/h rear sled tests than older (<2000 MY) designs and ABTS designs. The improved performance is consistent with an increase in seat strength combined with improved occupant kinematics through pocketing of the occupant into the seatback, higher and more forward head restraint, and other design changes. The methods and data presented here provide a basis for standardized testing of seats. However, a complete understanding of seat safety requires consideration of out-of-position (OOP) occupants in high-speed impacts and consideration of the much more common, low-speed rear impacts.  相似文献   

52.
Nanoparticles are now widely applied in products. The synthesis of nanomaterials using biological materials is an emerging field, notably for medical applications because biologically derived compounds can be safe. For instance, calcium phosphate is a natural biomineral that possesses an excellent biocompatibility due to its chemical similarity to human hard tissue such as bone and teeth. Here, we synthesized calcium phosphate nanoparticles by using bark extract of Spanish cherry (Mimusops elengi). Calcium phosphate nanoparticles showed an absorbance at 275 nm by UV–visible analysis and particle size of 25 nm by nanoparticle tracking and analysis. Fourier transform infrared spectroscopy revealed the presence of aromatic amines as a capping and reducing agent. Transmission electron microscopy showed the presence of polydispersed spherical nanoparticles with an average size of 50 nm. Measurements of zeta potential revealed the stability of the synthesized calcium phosphate nanoparticles. These particles demonstrated antibacterial activity against Streptococcus mutans, Staphylococcus aureus and Escherichia coli. We conclude that the synthesis of calcium phosphate nanoparticles by using a M. elengi is easy, eco-friendly and scalable.  相似文献   
53.
A review of incineration techniques for control of volatile organic compound emissions is presented in two consecutive issues of JAPC A. Part I presents an overview of the process including fundamentals and design considerations. Both thermal and catalytic incincerators are considered. Part II will present capital and annual operating cost estimates for both thermal and catalytic incinerator systems based on information received from a number of equipment manufacturers.  相似文献   
54.
We present here a study of the sintering of fly ash and its mixture with low alkali pyrophyllite in the presence of sodium hexa meta phosphate (SHMP), a complex activator of sintering, for the purpose of wall tile manufacturing. The sintering of fly ash with SHMP in the temperature range 925-1050 degrees C produces tiles with low impact strength; however, the incremental addition of low alkali pyrophyllite improves impact strength. The impact strength of composites with 40% (w/w) pyrophyllite in the fly ash-pyrophyllite mix satisfies the acceptable limit (19.6J/m) set by the Indian Standards Institute for wall tiles. Increasing the pyrophyllite content results in an increase in the apparent density of tiles, while shrinkage and water absorption decrease. The strength of fly ash tiles is attributed to the formation of a silicophosphate phase; in pyrophyllite rich tiles, it is attributed to the formation of a tridymite-structured T-AlPO(4) phase. Scanning electron micrographs show that the reinforcing rod shaped T-AlPO(4) crystals become more prominent as the pyrophyllite content increases in the sintered tiles.  相似文献   
55.
Arsenic poses a major environmental and human health problem because of its carcinogenic nature and effect on the ecosystem. Therefore, a cost effective and socially acceptable technique is needed for its remediation. The effect of different combinations of compost amended with zeolite and/or iron oxide (up to 20% w/w) was tested on a contaminated soil with high arsenic levels (34470 mg kg(-1)). The bioavailability of arsenic was determined in terms of uptake by rye grass (Lolium perenne L.) under greenhouse experimental conditions. The results indicated that the arsenic concentrations in the rye grass was reduced to 2 mg kg(-1) dry weight by using 15% compost with 5% iron oxide and 15% compost with 5% zeolite. Less than 0.01% of the total arsenic content in the soil was being taken up by the plants. Both treatments were effective in establishing significantly higher plant growth on the contaminated soil compared to other treatments. The results from sequential extraction tests indicated that in all the compost-amended soils, there was a reduction in the soluble fraction (10-37%). Arsenic in soil was examined using Scanning Electron Microscopy coupled with Energy Dispersive X-ray spectroscopy. The results indicated that arsenic was distributed mostly within the matrix of iron and oxygen in treated samples. Amongst various treatment mixtures tested, high percent of compost (15%) with zeolite (5%) and/or iron oxide (5%) is effective in reducing arsenic uptake by plants and establish re-vegetation on the contaminated soil.  相似文献   
56.
INTRODUCTION: This study investigated the survival rates of occupants of passenger cars involved in a fatal crash between 2000 and 2003. METHODS: The information from every fatal crash in the United States between 2000 and 2003 was analyzed. Variables such as seat position, point of impact, rollover, restraint use, vehicle type, vehicle weight, occupant age, and injury severity were extracted from the Fatality Analysis Reporting System (FARS). Univariate and a full logistic multivariate model analyses were performed. RESULTS: The data show that the rear middle seat is safer than any other occupant position when involved in a fatal crash. Overall, the rear (2(nd) row) seating positions have a 29.1% (Univariate Analysis, p<.0001, OR 1.29, 95% CI 1.22 - 1.37) increased odds of survival over the first row seating positions and the rear middle seat has a 25% (Univariate Analysis, p<.0001, OR 1.25, 95% CI 1.17 - 1.34) increased odds of survival over the other rear seat positions. After correcting for potential confounders, occupants of the rear middle seat have a 13% (Logistic Regression, p<.001, 95% CI 1.02 - 1.26) increased chance of survival when involved in a crash with a fatality than occupants in other rear seats. CONCLUSION: This study has shown that the safest position for any occupant involved in a motor-vehicle crash is the rear middle seat. IMPACT ON INDUSTRY: The results of this research may impact how automobile manufacturers look at future rear middle seat designs. If the rear seat was to be designed exactly like its outboard counterparts (headrest, armrests, lap and shoulder belt, etc.) people may choose to sit on it more often rather than waiting to use it out of necessity due to multiple rear seat occupants.  相似文献   
57.
The dysgnathia complex (agnathia-otocephaly) (AO) is a lethal malformation that consists of congenital absence of the lower jaw with union or close approximation of the lower ears on the front of the neck, microstomia, and hypoglossia. We present a novel case of agnathia-otocephaly with associated organomegaly and the use of postmortem 3-D computed tomographic rendering. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
58.

Increasing concentration of heavy metals (HMs) and polycyclic aromatic hydrocarbons (PAHs) in the soil may impose a serious threat to living organisms due to their toxicity and the ability to accumulate in plant tissues. The present review focuses on the phylogenetic relationships, sources, biotransformation and accumulation potential of hyperaccumulators for the priority HMs and PAHs. This review provides an opportunity to reveal the role of hyperaccumulators in removal of HMs and PAHs from soils, to understand the relationships between pollutants and their influence on the environment and to find potential plant species for soil remediation. The phylogenetic analysis results showed that the hyperaccumulators of some chemicals (Co, Cu, Mn, Ni, Zn, Cd) are clustered on the evolutionary tree and that the ability to hyperaccumulate different pollutants can be correlated either positively (Cd–Zn, Pb–Zn, Co–Cu, Cd–Pb) or negatively (Cu–PAHs, Co–Cd, Co–PAHs, Ni–PAHs, Cu–Ni, Mn–PAHs). Further research needs to be extended on the focus of commercializing the techniques including the native hyperaccumulators to remediate the highly contaminated soils.

  相似文献   
59.
Nootropic drugs like piracetam, oxiracetam, and nifiracetam are used as memory enhancers. They are thought to directly influence the energetic processes in the brain and produce elevated acetylcholine levels, but they lack protecting therapeutic potentials. Thus, there is a continuing effort directed towards developing a new cognition-enhancing agent, which would be more effective than the currently available drugs, and 2-Naphthyloxy derivatives (PP-20/DPJ) were consequently developed. This in vivo study was designed to compare the memory enhancing potential of PP-20/DPJ with the known nootropic agent, piracetam, in aluminum (Al)-induced neurotoxic model. Results indicated that PP-20/DPJ improved the short-term memory and cognitive behaviors similar to piracetam. Further, both the compounds were equally effective in elevating the acetylcholinesterase and Mg+-ATPase enzyme activity in both the brain regions after Al treatment. Thus the current study suggests, that PP-20/DPJ acts as both a cognition-enhancing agent and as a metabolic enhancer.  相似文献   
60.
The biosorption of heavy metals is considered to be one of the best alternatives for the treatment of wastewater. The metal binding capacity of algae and acid-treated algae is investigated to find out the removal characteristics of Cr(VI), Ni(II) and Cu(II) ions from single metal solutions. Batch experiments are conducted and the study is extended to investigate the effect of pH, amount of adsorbent and adsorbate concentration on the extent of biosorption. The results indicate that the adsorption capacity of algae depends strongly on pH. The maximum adsorption of Cr(VI), Ni(II) and Cu(II) occurs at pH values of 2, 7 and 4.3, respectively. The adsorption process follows first-order kinetic equation. The data obtained are correlated with Freundlich and Langmuir adsorption isotherms.  相似文献   
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