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591.
Environmental Fluid Mechanics - Linear stability analysis is used to investigate the behavior of small perturbations of a uniform flow in a straight channel with an erodible bed composed by a...  相似文献   
592.
Environmental Science and Pollution Research - The surface coating present on a marble Piety dating to the Renaissance period and stored at the Castello Sforzesco-Museum of Ancient Art (Milan,...  相似文献   
593.
Environmental Science and Pollution Research - Cyclodextrin nanosponges (CD-NS) are cross-linked cyclodextrin polymers characterized by a nanostructured three-dimensional network. CD-NSs in the...  相似文献   
594.
Journal of Material Cycles and Waste Management - In this work, the synthesis of biochar from several biomass wastes to act as matrix for urea was investigated. The objective was to select the most...  相似文献   
595.
Climate change severely impacts on the natural and socio-economic systems of the Pacific Islands. Samoa, a small insular state of the region, is characterized by widespread awareness of climate change reflected by its leading international role. This also makes Samoa a potentially exemplary reference for the Pacific Islands. Against this backdrop, the overall aim of this article is to investigate the notion of social vulnerability and measure its dimensions in Samoa through a specific index: the Samoa Social Vulnerability Index (SSVI). The SSVI may yield better understanding of the characteristics and dynamics of social vulnerability, as well as information for fostering adaptation strategies in Samoa and in the Pacific Islands. In particular, the article first outlines the major vulnerabilities to climate change in Samoa and then analyses the composite notion of social vulnerability. On this basis, the article methodologically specifies, designs and constructs the SSVI. Afterwards, it uses such index for measuring the dimensions of social vulnerability in Samoa’s districts. Finally, some considerations are made concerning the policy relevance of the SSVI and its potential regional role.  相似文献   
596.
Environmental Science and Pollution Research - The installation of district heating (DH) systems constitutes an advantage from the energetic, climate, and air quality aspects. However, the...  相似文献   
597.
There is a growing market demand for small-scale biomass gasifiers that is driven by the economic incentives and the legislative framework. Small-scale gasifiers produce a gaseous fuel, commonly referred to as producer gas, with relatively low heating value. Thus, the most common energy conversion systems that are coupled with small-scale gasifiers are internal combustion engines. In order to increase the electrical efficiency, the operators choose dual fuel engines and mix the producer gas with diesel. The Wiebe function has been a valuable tool for assessing the efficiency of dual fuel internal combustion engines. This study introduces a thermodynamic model that works in parallel with the Wiebe function and calculates the emissions of the engines. This “vis-à-vis” approach takes into consideration the actual conditions inside the cylinders—as they are returned by the Wiebe function—and calculates the final thermodynamic equilibrium of the flue gases mixture. This approach aims to enhance the operation of the dual fuel internal combustion engines by identifying the optimal operating conditions and—at the same time—advance pollution control and minimize the environmental impact.  相似文献   
598.
Objective: Autonomous emergency braking (AEB) acts to slow down a vehicle when an unavoidable impending collision is detected. In addition to documented benefits when applied to passenger cars, AEB has also shown potential when applied to motorcycles (MAEB). However, the feasibility of MAEB as practically applied to motorcycles in the real world is not well understood.

Methods: In this study we performed a field trial involving 16 riders on a test motorcycle subjected to automatic decelerations, thus simulating MAEB activation. The tests were conducted along a rectilinear path at nominal speed of 40 km/h and with mean deceleration of 0.15 g (15% of full braking) deployed at random times. Riders were also exposed to one final undeclared brake activation with the aim of providing genuinely unexpected automatic braking events.

Results: Participants were consistently able to manage automatic decelerations of the vehicle with minor to moderate effort. Results of undeclared activations were consistent with those of standard runs.

Conclusions: This study demonstrated the feasibility of a moderate automatic deceleration in a scenario of motorcycle travelling in a straight path, supporting the notion that the application of AEB on motorcycles is practicable. Furthermore, the proposed field trial can be used as a reference for future regulation or consumer tests in order to address safety and acceptability of unexpected automatic decelerations on a motorcycle.  相似文献   

599.

Objective

To evaluate fetal brain development using MRI (magnetic resonance imaging) in CDH (congenital diaphragmatic hernia).

Methods

52 isolated left CDH and 104 control fetuses were imaged using MRI. Brain morphometry (Biparietal diameter—BPD, brain fronto-occipital diameter—BFOD, third ventricle, posterior ventricles, transcerebellar diameter—TCD, anteroposterior and craniocaudal cerebellar vermis diameter—AP and CC) and cortical structures (bilateral cingulate fissure—CF, insular fissure—IF, insular depth - ID) were compared with controls using Mann–Whitney test.

Results

Median gestational age at MRI (p = 0.95)and the median biparietal diameter (p = 0.737) were comparable. Among morphometric parameters, only the brain fronto-occipital diameter was significantly smaller in CDH (p = 0.001) and the third ventricle was significantly greater in CDH (<0.0001). Among cortical structures, the cingulate and insular fissures were significantly deeper in CDH fetuses (p < 0.0001) as the insular depth ID was smaller in CDH (p < 0.03).

Conclusions

CDH fetuses have a smaller fronto-occipital diameter, reduced insular depth, deeper cingulate and insular fissure, and greater third ventricle width as compared to controls. These findings suggest that left CDH may have an impact on fetal brain development with an overall reduction in brain volume.  相似文献   
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