Effects of pretreatment methods on solubilization of beet-pulp and bio-hydrogen production yield,” Int

a b s t r a c t Sugar processing wastewater and beet-pulp are two major waste streams of sugar-beet processing plants. Contrary to wastewater, beet-pulp is generally used as animal feed in cattle-raising industry. However, it can serve as a substrate for bio-hydrogen production which corresponds to a higher valorization of beet-pulp. Moreover, pretreatment of lignocellulosic materials like beet-pulp is needed in order to improve overall energy efficiency and enable economic feasibility of bio-hydrogen production. Therefore, the effect pretreatment methods (alkaline, thermal, microwave, thermal-alkaline and microwavealkaline) on bio-hydrogen production from sugar beet-pulp through dark fermentation were investigated in this study. Reactors pretreated with alkaline, microwave-alkaline and thermal-alkaline methods yielded significant solubilization of beet-pulp compared to others. Therefore, in the second phase of the study, they were used to pretreat the beetpulp which was then subjected to dark fermentation for bio-hydrogen production. Maximum bio-hydrogen production yield of 115.6 mL H 2 /g COD was observed in reactor which contained alkaline pretreated beet-pulp. ª 2010 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved. Introduction Hydrogen is a clean and environmentally friendly fuel since the combustion of hydrogen produces only water vapor instead of greenhouse gases like CO 2 . Furthermore, hydrogen has a high energy yield of 122 kJ/g, which is about 2.75 times greater than that of hydrocarbon fuels From the perspective of global environmental impacts, such as greenhouse effect and resource recovery, biological hydrogen production from renewable biomass reduces dependence on fossil fuel, decrease carbon dioxide emission and recovers bio-energy. Moreover, in order to establish Abbreviations: AD, Anaerobic Digestion; BES, 2-Bromoethanesulfonate; BM, Basal Medium; COD, Chemical Oxygen Demand; GC, Gas Chromatograph; HeAc, Acetic Acid; H-Bu, n-Butyric Acid; HePr, Propionic Acid; HRT, Hydraulic Retention A v a i l a b l e a t w w w . s c i e n c e d i r e c t . c o m j o u r n a l h o m e p a g e : w w w . e l s e v i e r . c o m / l o c a t e / h e i n t e r n a t i o n a l j o u r n a l o f h y d r o g e n e n e r g y 3 6 ( 2 0 1 1 ) 3 8 2 e3 8

Porous metal-organic Cu II complex of L-Arginine; synthesis, characterization, hydrogen storage properties and molecular simulation calculations

Cu II -arginine coordination compound was synthesized and characterized by using DSC, DTA, EA, FT-IR, XRD, SEM and EDX analysis techniques and then the hydrogen storage properties were investigated. Hydrogen storage performance of synthesized compound was determined both experimental and theoretically by using Materials Studio which is one of the Molecular simulation software and adsorption measurement equipment. It is found out that the arginine compound uptakes approximately 1.2 wt. % experimentally and 0.8 wt. % theoretically hydrogen in 77K and 100 bars pressure. Also the surface characteristics was calculated and also the possible cites which could uptake hydrogen in a single lattice cell were determined. At the end of this research, in addition to drug and other applications of L-arginine, it is proved that could be used as a part of adsorbent for hydrogen storage application

Determination of optimal synthesis conditions of porous styrene divinyl benzene copolymer beads in the presence of the ammonia borane

In this study, optimal synthesis conditions of important industrial polymer of porous styrene divinylbenzene copolymer (SDVB) beads are investigated in the presence of the ammonia borane in order to increase the porosity of the microspheres. In that purpose, benzoyl peroxide as radical initiator, polyvinyl alcohol (PVA) as stabilization, sodium hydroxide (NaOH), toluene and hexane as organic diluent are used by suspension polymerization. In addition to initiator, different quantities of ammonia borane (AB) are used. In experimental studies, polymerization reaction is carried out under nitrogen atmosphere at 80 degrees C and at atmospheric pressure. As results of parametric studies, copolymer beads are characterized by the surface area and porosity (BET), Fourier transform infrared spectrometry (FTIR), swelling analysis by wet method. It is seen that synthesized copolymers used AB contribute to pore generation and particular size distribution, as DVB percent increases, polymer efficiency increases but swelling percent decreases. By using RSM (Response Surface Method), according to central composite design method, optimum conditions are calculated as 90\%DVB; 0, 05 g ammonia borane; 200\% solvent quantity and under these conditions, BET surface area of synthesized copolymers is found as156 m(2)/g. As a result of surface modification with acetone, surface area is increased to 274 m(2)/g

Spatial domain reconstruction for imaging speed-of-sound with pulse-echo ultrasound: simulation and in vivo study

Despite many uses of ultrasound, some pathologies such as breast cancer still cannot reliably be diagnosed in either conventional B-mode ultrasound imaging nor with more recent ultrasound elastography methods. Speed-of-sound (SoS) is a quantitative imaging biomarker, which is sensitive to structural changes due to pathology, and hence could facilitate diagnosis. Full-angle ultrasound computed tomography (USCT) was proposed to obtain spatially-resolved SoS images, however, its water-bath setup involves practical limitations. To increase clinical utility and for widespread use, recently, a limited-angle Fourier-domain SoS reconstruction was proposed, however, it suffers from significant image reconstruction artifacts. In this work, we present a SoS reconstruction strategy, where the forward problem is formulated using differential time-of-flight measurements based on apparent displacements along different ultrasound wave propagation paths, and the inverse problem is solved in spatial-domain using a proposed total-variation scheme with spatially-varying anisotropic weighting to compensate for geometric bias from limited angle imaging setup. This is shown to be robust to missing displacement data and easily allow for incorporating any prior geometric information. In numerical simulations, SoS values in inclusions are accurately reconstructed with 90% accuracy up to a noise level of 50%. With respect to Fourier-domain reconstruction, our proposed method improved contrast ratio from 0.37 to 0.67 for even high noise levels such as 50%. Numerical full-wave simulation and our preliminary in vivo results illustrate the clinical applicability of our method in a breast cancer imaging setting. Our proposed method requires single-sided access to the tissue and can be implemented as an add-on to conventional ultrasound equipment, applicable to a range of transducers and applications

Spatial domain reconstruction for imaging speed-of-sound with pulse-echo ultrasound: simulation and in vivo study

Despite many uses of ultrasound, some pathologies such as breast cancer still cannot reliably be diagnosed in either conventional B-mode ultrasound imaging nor with more recent ultrasound elastography methods. Speed-of-sound (SoS) is a quantitative imaging biomarker, which is sensitive to structural changes due to pathology, and hence could facilitate diagnosis. Full-angle ultrasound computed tomography (USCT) was proposed to obtain spatially-resolved SoS images, however, its water-bath setup involves practical limitations. To increase clinical utility and for widespread use, recently, a limited-angle Fourier-domain SoS reconstruction was proposed, however, it suffers from significant image reconstruction artifacts. In this work, we present a SoS reconstruction strategy, where the forward problem is formulated using differential time-of-flight measurements based on apparent displacements along different ultrasound wave propagation paths, and the inverse problem is solved in spatial-domain using a proposed total-variation scheme with spatially-varying anisotropic weighting to compensate for geometric bias from limited angle imaging setup. This is shown to be robust to missing displacement data and easily allow for incorporating any prior geometric information. In numerical simulations, SoS values in inclusions are accurately reconstructed with 90% accuracy up to a noise level of 50%. With respect to Fourier-domain reconstruction, our proposed method improved contrast ratio from 0.37 to 0.67 for even high noise levels such as 50%. Numerical full-wave simulation and our preliminary in vivo results illustrate the clinical applicability of our method in a breast cancer imaging setting. Our proposed method requires single-sided access to the tissue and can be implemented as an add-on to conventional ultrasound equipment, applicable to a range of transducers and applications.ISSN:1361-6560ISSN:0031-915

Robust motion tracking in liver from 2D ultrasound images using supporters

ISSN:1861-6410ISSN:1861-642

Development of a Surgical Interface for Cryoablation of Kidney Tumors

Autonomous surgical systems aim to improve surgical treatments in all stages of the clinical workflow. A surgical interface should be safe, robust, and user-friendly. In this article, the functionality and usability of a surgical interface as critical factors for acceptability are investigated. Then, the surgical interface for the cryoablation of kidney tumors is designed, with consideration of the functionality and usability factors. The surgical interface includes a preoperative surgical simulator that allows the surgeon to plan the surgical interventions. The surgical interface with one surgeon is evaluated