Vibroacoustic frequency response on a passenger compartment

The paper presents frequency response analysis at the passenger compartment level followed by an acoustic analysis performed by means of finite element method. Normal mode analysis of the body in white (BIW) was performed and the eigenvectors presented. A frequency-dependent velocity excitation profile in vertical direction at the front and rear axles were considered for the frequency response analysis. The acceleration response at three driver comfort points was recorded as well. Subsequently, in the coupled fluid-structure frequency response analysis the calculation of sound pressure level (SPL) variation as a function of the same frequency-dependent load was conducted at the driver and rear passenger ear locations. The paper is finalized with conclusions on the comfort driver points and sound pressure levels as response to the in-phase and out-of-phase frequency dependent excitation. This analysis is a prerequisite for structural panel participation and structure optimizatio

Vibroacoustic frequency response on a passenger compartment

The paper presents frequency response analysis at the passenger compartment level followed by an acoustic analysis performed by means of finite element method. Normal mode analysis of the body in white (BIW) was performed and the eigenvectors presented. A frequency-dependent velocity excitation profile in vertical direction at the front and rear axles were considered for the frequency response analysis. The acceleration response at three driver comfort points was recorded as well. Subsequently, in the coupled fluid-structure frequency response analysis the calculation of sound pressure level (SPL) variation as a function of the same frequency-dependent load was conducted at the driver and rear passenger ear locations. The paper is finalized with conclusions on the comfort driver points and sound pressure levels as response to the in-phase and out-of-phase frequency dependent excitation. This analysis is a prerequisite for structural panel participation and structure optimizatio

Nano- and Micro-scale Structures

IASS-IACM 2008 Session: Nano- and Micro-scale Structures -- Session Organizers: Slava KRYLOV (Tel Aviv Univ.), Alan ZEHNDER (Cornell Univ.) -- Plenary Lecture: Abstract, Slides and Video: "Nanomechanical resonators and nanofluidic systems" by Harold G. CRAIGHEAD (Cornell University) -- Keynote Lecture: "An atomistic-continuum elastic rod model of carbon nanotubes" by Karthick CHANDRASEKER, Subrata MUKHERJEE (Cornell University) -- "A novel shift-loaded blister test to characterize the multi-scale mechanical properties and adhesion-delamination behaviors of biomembranes" by Scott E. JULIEN (Northeastern University), Kuo-Kang LIU (Keele University), Kai-tak WAN (Northeastern University) -- "Hybrid sensing procedure for mass and position detection with nano and macro resonant cantilevers" by Nicolae LOBONTIU (University of Alaska Anchorage), Iulian LUPEA, Rob ILIC, Harold G. CRAIGHEAD (Cornell University) -- "Stability analysis of a curved microbeam actuated by a distributed electrostatic force" by Slava KRYLOV (Tel Aviv University), Bojan R. ILIC (Cornell University), David SCHREIBER, Shimon SERETENSKY (Tel Aviv University), Harold G. CRAIGHEAD (Cornell University) -- Keynote Lecture: "On the accuracy of compliant mechanical MEMS/NEMS lumped-parameter modeling" by Nicolae LOBONTIU (University of Alaska Anchorage) -- "The response of a cantilever microbeam with a plate attached to its tip to mechanical shock" by Hassen OUAKAD (Binghamton University), Haider N. ARAFAT (Cessna Aircraft Company), Mohammad I. YOUNIS (Binghamton University) -- "Switch triggered by mass threshold" by Mohammad I. YOUNIS , Fadi M. AL SALEEM (Binghamton University) -- "Adhesion of freestanding beams and its application to micro- and nano-structures" by Kai-tak WAN (Northeastern University) -- "Modeling and dynamics of coupled dome-shaped micromechanical oscillators" by Tuhin SAHAI, Alan ZEHNDER (Cornell University) -- "Fully Lagrangian dynamics of thin MEMS beam" by Ranajay GHOSH , Subrata MUKHERJEE (Cornell University

Kinetic and equilibrium studies for cadmium biosorption from contaminated water using Cassia fistula biomass

Cadmium (Cd) contamination of the water resources is one of the serious environmental issues. The present study aims to (1) evaluate the biosorption potential of Cassia fistula biomass for the removal of Cd from contaminated water and validate the experimental results with kinetic and equilibrium sorption models, (2) assess the removal of Cd from groundwater samples in the presence of other competing ions in the solution. The C. fistula biomass was characterized using Fourier transform infrared spectroscopy, Brunauer–Emmett–Teller technique and scanning electron microscopy to understand the role of its physical properties in Cd biosorption and removal. The effects of biosorbent dose, initial Cd concentrations, contact time and presence of competing cations in groundwater samples at constant pH and temperature (27 ± 1.5 °C) were studied. At equilibrium (90 min), Cd removal (98–16%) and biosorption (6.26–0.34 mg/g) were recorded depending on the experimental conditions. The Langmuir model yielded a better approximation of the experimental data at equilibrium (Formula presented.) rather than Freundlich model. The pseudo-second-order kinetic model explained well the kinetic behavior of Cd biosorption. Results revealed a decline in the Cd removal (12.7 and 6% at 0.25 and 1.0 g/100 mL, respectively) in the presence of cations in the water samples. The results proved that C. fistula is a very effective and environment friendly alternative adsorbent for the removal (98%) of Cd from the aqueous system

Hydroalcoholic extracts from the bark of Quercus suber L. (Cork): optimization of extraction conditions, chemical composition and antioxidant potential

Cork is the bark of the tree Quercus suber L. which ï¬ nds use in diverse applications. However, a signiï¬ cant percentage is still rejected and burned for energy production, despite containing valuable molecules for materials processing and with important biological activities. Herein, the optimization of the extraction process to obtain these molecules, using mild solvents and conditions, is described within a bioreï¬ nery perspective. The extracts were obtained by direct contact solvent extractions with water, ethanol and its mixtures for different time and temperatures, and evaluated for chemical composition, total phenolic content (TPC) and antioxidant properties [by DPPH radical scavenging, ferric reducing antioxidant power (FRAP), Trolox equivalent antioxidant capacity (TEAC) and oxygen radical absorbance capacity (ORAC) assays]. The results showed that the extraction process is accelerated and higher yields are achieved with the increase in temperature without chemical degradation or compromising the antioxidant capacity. For all solvents, at reï¬ ux temperature, more than 90% of the extractable material is obtained within 6 h (80% within 1 h). The highest TPC and antioxidant capacity are observed for the extracts obtained with mixtures of water and ethanol of similar volumes. The antioxidant capacity measured by DPPH, FRAP and TEAC assays was found to be proportional to the extract TPC, while ORAC is favored for higher percentages of ethanol on the extracting solvent. The main constituents of these extracts are the ellagitannins, vescalagin, castalagin and b-O-ethylvescalagin, along with other phenolic acids (mainly ellagic and gallic acids) and various ï¬ avonols. The extracts stability was monitored up to 1 year of storage with neither reduction in the antioxidant capacity nor chemical degradation. These results show that extracts with strong antioxidant potential and high content of bioactive molecules can be obtained from the processing of waste streams. Cork is a sustainable forest product and the development of new ï¬ elds of application contributes toward a zero waste cycle for a complete material bioreï¬ nery.The authors are grateful to Amorim Cork Composites for providing the cork powder and for the financing provided by the COMPETE/QREN/EU funding program through project BioActiveCork (QREN FCOMP-01-0202-FEDER-005455). Ivo M. Aroso and João P. Fernandes Fig. 6 Comparison between fresh and 1 year stored extracts for a TPC and b DPPH scavenging capacity Wood Sci Technol123 acknowledge the financial support from FCT through grants SFRH/BD/42273/2007 and SFRH/BD/73162/2010, respectively. Funding was also granted from the European Union’s Seventh Framework Programme (FP7/2007–2013) under Grant Agreement No. REGPOT-CT2012-316331-POLARIS and from Project ‘‘Novel smart and biomimetic materials for innovative regenerative medicine approaches (Ref.: RL1 - ABMR - NORTE-01-0124-FEDER-000016)’’ co-financed by North Portugal Regional Operational Programme (ON.2 – O Novo Norte), under the National Strategic Reference Framework (NSRF), through the European Regional Development Fund (ERDF). Conflict of Interest: The authors declare that they have no conflict of interest.info:eu-repo/semantics/publishedVersio