Design and implementation of the new D0 level-1 calorimeter trigger Abolins, M.; Adams, M.; Adams, T. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
2008, 2008-1-00, Letnik:
584, Številka:
1
Journal Article
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Increasing luminosity at the Fermilab Tevatron collider has led the D0 collaboration to make improvements to its detector beyond those already in place for Run IIa, which began in March 2001. One of ...the cornerstones of this Run IIb upgrade is a completely redesigned level-1 calorimeter trigger system. The new system employs novel architecture and algorithms to retain high efficiency for interesting events while substantially increasing rejection of background. We describe the design and implementation of the new level-1 calorimeter trigger hardware and discuss its performance during Run IIb data taking. In addition to strengthening the physics capabilities of D0, this trigger system will provide valuable insight into the operation of analogous devices to be used at LHC experiments.
The New DØ Level-1 Calorimeter Trigger Abolins, M.; Adams, M.; Adams, T. ...
2006 IEEE Nuclear Science Symposium Conference Record,
2006-Oct., Letnik:
3
Conference Proceeding
With increasing Tevatron luminosity, efficient triggers that meet the bandwidth limitations of the experiment's data acquisition system become more and more difficult to construct. To meet these ...challenges, the DOslash experiment has significantly enhanced its triggering capabilities. A major component of this upgrade is a completely re-designed Level-1 calorimeter trigger (L1Cal). This new system uses novel architecture and algorithms to maintain acceptable background rejection while preserving or even improving signal efficiency at the highest luminosities foreseen. We describe interesting features of the L1Cal and give highlights from its first few months of operation.
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•Pretreatments are important in a combined biorefinery aspect with different waste resources.•Components of substrates are taken in account to improve pretreatment ...efficiency.•Combined pretreatment is a suitable solution to improve the digestibility.•Biogas yield and energy balance should be considered for the effects of pretreatments.
Biogas production from different waste resources still has limitations due to its complex structure and slowly biodegradable nature. To improve methane yield and anaerobic digestion performance, various substrate pretreatment methods have been suggested. This paper reviews the latest trends, progress, and research achievements about pretreatment technologies to improve anaerobic digestion efficiency. The pretreatment techniques are divided into four main groups which are physical, chemical, biological, and combined. The effect of inhibitor formation during the pretreatment process is discussed. The energy performance, economics, and environmental impact of these pretreatment technologies are revealed. This study concludes with future trends and emphasizes the necessity of pretreatment methods.
One-dimensional nanostructures, such as nanorod (NR) arrays, are expected to improve the photovoltaic (PV) response of solar cells with an ultrathin absorber due to an increased areal (junction) ...density and light trapping. We report on the deposition of CdS and CdTe:As semiconductor thin films on ZnO NR arrays by means of metalorganic chemical vapour deposition (MOCVD). The change in optical properties of the ZnO NRs upon the growth of CdS shell was monitored and compared to the simulated data, which confirmed the presence of strong light scattering effects in the visible and near infrared regions. The PV performance of nanostructured vs. planar CdS/CdTe solar cells (grown using the material from the same MOCVD run) showed similar conversion efficiencies (~ 4%), despite the current density being lower for the nanostructured cell due to its thicker CdS window. A clear improvement in the quantum efficiency was however observed in the near infrared region, resulting from the light trapping by the ZnO/CdS core-shell NR structure. We also showed that reduction of surface defects and use of high absorber carrier density would boost the efficiency beyond that of planar CdTe solar cells. The reported device performance and the direct observation of light trapping are promising towards optimisation of extremely-thin-absorber CdTe PV devices.
•Extremely thin absorber CdTe thin film solar cells fabricated using ZnO nanorod array films.•Conformal growth of CdS and CdTe shells on ZnO nanorods achieved by MOCVD.•Optical properties and light trapping were studied experimentally and theoretically.•Over 4% conversion efficiency reported using less than 0.5µm CdTe absorber.
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•ANN model was used to simulate for prediction and maximization of ACd.•Bayesian Regularization algorithm showed the best performance.•According to the ANN model, the co-digestion ...might improve the methane yield up to 183% compared to mono substrates.
The production of biofuel from waste has become an important topic for waste management and reducing its environmental hazard. Tea factory waste is a strong candidate due to its availability and sourceability. This study aimed to reveal the biochemical methane potential (BMP) of tea factory waste (TFW) and spent tea waste (STW). Additionally, the results revealed that both substrates had high biodegradability due to high VS removal. The BMP tests took 49 days under mesophilic conditions with a batch reactor and the cumulative methane yields were 249 ± 3, and 261 ± 8 mL CH4/g VS for TFW and STW, respectively. According to prediction data with the selected ANN model, which was 50 hidden layer sizes, trained with Bayesian Regularization algorithm, the maximum cumulative specific methane yield of the co-digestion was simulated as 468.43 mL CH4/g VS when the ratio of 65 and 35% (w/w by VS) of TFW and STW, respectively. The predicted methane yield for co-substrates was 183% higher than mono substrates. This result revealed that TFW can be a good candidate for biogas production as biofuel for not only its availability and sourceability but also the synergistic effect possible for co-digestion.
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•The extraction of oil was used for SCGs as a pretreatment method for AD.•DSCGs outperform SCGs according to BMP as well as TS and VS removal.•Enhancement of CH4 yield was obtained ...when the percentage of DSCG was increased.
The effect of oil extraction from spent coffee grounds as a pre-treatment strategy prior to anaerobic digestion besides assessing the feasibility of defatted spent coffee grounds co-digestion with spent tea waste, glycerin, and macroalgae were examined. Mesophilic BMP tests were performed using defatted spent coffee grounds alongside four co-substrates in the ratio of 25, 50, and 75%, respectively. The highest methane yield was obtained with the mono-digestion of defatted spent coffee grounds with 336 ± 7 mL CH4/g VS and the yield increased with the increase in the mass ratio of defatted spent coffee grounds during co-digestion. Moreover, defatted spent coffee grounds showed the highest VS and TS removal at 35.5% and 32.1%, respectively and decreased thereafter. Finally, a linear regression model for the interaction effects between substrates was demonstrated and showed that distinctly mixing defatted spent coffee grounds, spent coffee grounds, and spent tea waste outperforms other triple mixed substrates.
Rubidium (Rb) has been shown to impact biological activity. This work synthesized Rb-doped mesoporous bioactive glass nanoparticles (MBGNs) based on the composition 70SiO
2
–30CaO mol% with a sol-gel ...method. Rb
2
O was substituted for CaO in concentrations of 5 and 10 mol%. The influence of Rb incorporation on the hydroxycarbonate apatite (HCA) formation, cytotoxicity, and antibacterial capacity of particles was evaluated. XRD analysis confirmed the amorphous structure of the particles. In vitro, biomineralization studies showed HCA on the surface of MBGN and Rb-doped MBGN pellets after 7 days of soaking in simulated body fluid (SBF). An inhibition zone of
Escherichia coli (E.coli)
and
Staphylococcus aureus (S. aureus)
around Rb-doped MBGN pellets was detected, while MBGN pellets did not show any inhibition zone. Additionally, MC3T3-E1 pre-osteoblastic cells demonstrated cytocompatibility when exposed to Rb-MBG suspensions at different concentrations of up to 250 µg/ml. Based on their overall properties, Rb-containing MBGNs are proposed for biomedical applications, such as filler nanoparticles in composite bone scaffolds.
Anaerobic digestion (AD) from organic waste has gained worldwide attention in reducing greenhouse gas emissions, lowering fossil fuel combustion, and facilitating a sustainable renewable energy ...supply. Biogas mainly consists of methane (CH
4
) (50–75%), carbon dioxide (CO
2
) (25–50%), hydrogen sulphides (H
2
S), hydrogen (H
2
), ammonia (NH
3
) (1–2%) and traces of other gases such as oxygen (O
2
) and nitrogen (N
2
). Methane can replace fossil fuels in various applications such as heat and power generation and the transportation sector. The degradation of organic waste through an AD process offers many advantages, such as the decrease of pathogens and prevention of odour release. The digestate from anaerobic fermentation is a valuable fertilizer, however, the amount of organic materials currently available for biogas production is still limited. New substrates, as well as more effective conversion technologies, are needed to grow this industry globally. This paper reviewed the latest trends and progress in biogas production technologies including potential feedstock. Recycling of waste has recently become an important topic and has been explored in this paper.
The use of essential oils (EOs) combined with engineered biomaterials has been continuously growing. Research has focused on counteracting drawbacks of EOs such as volatility, relative low stability, ...and high sensitivity to environmental factors, in addition to investigating biological effects of EOs. This review discusses recent developments in the use of EOs in biomedical applications, such as antibacterial materials, drug delivery systems, and wound healing. Furthermore, we summarize not only the antibacterial and biological activities of biomaterial–EO combinations, but also discuss the effects of EOs on physical, thermal, and mechanical properties of biomaterials, which distinguishes this review from previous similar articles. EOs discussed are cinnamon, clove, and peppermint. Results show that the incorporation of EOs in engineered biomaterials has led to improved antibacterial activity, biocompatibility, and wound healing in several systems. Biomaterial–EO combinations represent a promising alternative for a new generation of hybrid biomedical systems incorporating natural medicinal compounds in engineered biomaterials.
The aim of this study was to fabricate and characterize various concentrations of peppermint essential oil (PEP) loaded on poly(ε-caprolactone) (PCL) electrospun fiber mats for healing applications, ...where PEP was intended to impart antibacterial activity to the fibers. SEM images illustrated that the morphology of all electrospun fiber mats was smooth, uniform, and bead-free. The average fiber diameter was reduced by the addition of PEP from 1.6 ± 0.1 to 1.0 ± 0.2 μm. Functional groups of the fibers were determined by Raman spectroscopy. Gas chromatography-mass spectroscopy (GC-MS) analysis demonstrated the actual PEP content in the samples.
degradation was determined by measuring weight loss and their morphology change, showing that the electrospun fibers slightly degraded by the addition of PEP. The wettability of PCL and PEP loaded electrospun fiber mats was measured by determining contact angle and it was shown that wettability increased with the incorporation of PEP. The antimicrobial activity results revealed that PEP loaded PCL electrospun fiber mats exhibited inhibition against
(gram-positive) and
(gram-negative) bacteria. In addition, an
cell viability assay using normal human dermal fibroblast (NHDF) cells revealed improved cell viability on PCL, PCLPEP1.5, PCLPEP3, and PCLGEL6 electrospun fiber mats compared to the control (CNT) after 48 h cell culture. Our findings showed for the first time PEP loaded PCL electrospun fiber mats with antibiotic-free antibacterial activity as promising candidates for wound healing applications.
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