The implementation of oxyfuel carbon capture and storage technologies in combination with use of alternative fuels comprising high biogenic shares is promoted as an attractive climate change ...mitigation option for the cement sector to achieve low or even negative carbon emissions. Here, we perform a prospective life cycle assessment of two state-of-the art cement plants, one in Sweden and one in Germany, under conventional and retrofitted oxyfuel conditions considering alternative fuel mixes with increasing bio-based fractions of forest residues or dedicated bioenergy crops. The analysis also considers effects of the projected changes in the electricity systems up to 2050. Retrofitting the cement plants to oxyfuel reduces climate change impacts between 74 and 91%, while with additional use of biomass as alternative fuel the cement plants reach negative emission between - 24 and - 169 gCO
kg
, depending on operational condition, location, and biomass type. Additional emission reduction of - 10 (Sweden) and - 128 gCO
kg
(Germany) are expected from the decarbonization of the future electricity systems. Retrofitting the cement plants to oxyfuel conditions shows trade-offs with other environmental impacts (e.g., human toxicity, water and energy depletion), which are partially offset with projected changes in electricity systems. Our results illustrate the large climate change mitigation potential in the cement sector that can be achieved by the implementation of oxyfuel carbon capture and storage and biomass use as alternative fuel.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Although vocal signals including human languages are composed of a finite number of acoustic elements, complex and diverse vocal patterns can be created from combinations of these elements, linked ...together by syntactic rules. To enable such syntactic vocal behaviors, neural systems must extract the sequence patterns from auditory information and establish syntactic rules to generate motor commands for vocal organs. However, the neural basis of syntactic processing of learned vocal signals remains largely unknown. Here we report that the basal ganglia projecting premotor neurons (HVC(X) neurons) in Bengalese finches represent syntactic rules that generate variable song sequences. When vocalizing an alternative transition segment between song elements called syllables, sparse burst spikes of HVC(X) neurons code the identity of a specific syllable type or a specific transition direction among the alternative trajectories. When vocalizing a variable repetition sequence of the same syllable, HVC(X) neurons not only signal the initiation and termination of the repetition sequence but also indicate the progress and state-of-completeness of the repetition. These different types of syntactic information are frequently integrated within the activity of single HVC(X) neurons, suggesting that syntactic attributes of the individual neurons are not programmed as a basic cellular subtype in advance but acquired in the course of vocal learning and maturation. Furthermore, some auditory-vocal mirroring type HVC(X) neurons display transition selectivity in the auditory phase, much as they do in the vocal phase, suggesting that these songbirds may extract syntactic rules from auditory experience and apply them to form their own vocal behaviors.
Sugarcane straw has become available in large quantities in the field due to transition from manual to mechanical harvesting. Straw can be used as fuel for cogeneration systems of sugarcane mills to ...increase surplus electricity for commercialization. However, the exploitation of straw potential is still limited due to some challenges related to its agricultural recovery and industrial processing. The retrofit (additional installation) of existing sugarcane mills to process straw is an alternative to reduce investment and to allow a gradual utilization of this biomass. In this work, techno-economic and environmental assessment of straw recovery through bale system to increase electricity export was assessed. Two scenarios with straw recovery and processing were defined to take advantage of an existing cogeneration system, considering its operation in the season and off-season periods. An increase of up to 57% on surplus electricity was achieved. Both scenarios resulted in economically feasible alternatives. However, results were very sensitive to the variations on electricity prices and straw costs. In terms of environmental benefits, the bioelectricity presented a great potential to mitigate greenhouse gas emissions compared with natural gas–based electricity. The higher electricity surplus also affects the carbon intensity of ethanol, which can lead to indirect gains when the Brazilian program for biofuels incentive is implemented.
Spin precession with frequencies up to 280 GHz is observed in Mn(3-δ)Ga alloy films with a perpendicular magnetic anisotropy constant K(u)∼15 M erg/cm(3). The damping constant α, characterizing ...macroscopic spin relaxation and being a key factor in spin-transfer-torque systems, is not larger than 0.008 (0.015) for the δ=1.46 (0.88) film. Those are about one-tenth of α values for known materials with large K(u). First-principles calculations well describe both low α and large K(u) for these alloys.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
Unconventional superconductivity is usually associated with a layered system. But how thin can a layered superconductor be and continue to be superconducting? Painstakingly grown superlattices of the ...heavy-fermion superconductor CeCoIn5 suggest it could be as thin as a single layer.
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IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
•Nutritional background before adaptation period had no effect on adaptation length.•Nutritional restriction before adaptation period improved feedlot performance.•Intake of concentrate before ...adaptation period increased hot carcass weight.
The study was designed to evaluate the effects of either nutritional restriction or intake of concentrate feedstuffs before beginning the adaptation period on days to adapt, feedlot performance, feeding behavior, carcass characteristics, rumen and cecum morphometric of Nellore cattle. The experiment was designed as a completely randomized block, replicated 8 times (4 animals/pen), in which 96 Nellore bulls with an initial body weight (BW) of 365.52 ± 39.19 kg were fed in 24 pens according to the treatments, as follows: Restriction (Tifton hay fed at 1.4% of BW + mineral supplement); Control (Tifton hay fed ad libitum + mineral supplement) and Concentrate (Tifton hay fed ad libitum + 0.5% of BW of a mix of concentrate feedstuffs and mineral supplement). This study lasted 144-d, divided into 2 periods, as follows: 32-d of preadaptation, in which cattle were submitted to the treatments previously described, and 112-d of finishing period, where all cattle were fed the same diets. At the end of preadaptation period, one animal per pen was slaughtered (n = 24) for carcass, cecum and rumen evaluations, and the remaining 72 animals were harvested after 112-d of finishing period. No significant (P > 0.10) treatment effect was observed for days to adapt to the high-concentrate diet, which was 14 days (SEM: 0.63). Cattle submitted to restriction had greater (P < 0.10) ADG in kg (Restriction: 1.29; Control: 1.06; Concentrate: 1.18; SEM: 0.04), DMI in kg (Restriction: 9.19; Control: 8.56; Concentrate: 8.86; SEM: 0.28), G:F ratio (Restriction: 0.140; Control: 0.124; Concentrate: 0.133; SEM: 0.004), number of papillae (Restriction: 72.76; Control: 63.28; Concentrate: 62.99; SEM: 3.41) and absorptive surface area in cm2 of rumen wall (Restriction: 26.89; Control: 22.29; Concentrate: 22.30; SEM: 1.36) compared with cattle in the control group at the end of the study. Cattle submitted to either restriction or concentrate supplementation had greater (P < 0.10) final HCW in kg (Restriction: 285.35; Control: 274.10; Concentrate: 287.30; SEM: 4.51), final 12th rib fat in mm (Restriction: 4.57; Control: 3.93; Concentrate: 4.50; SEM: 0.21) and final Biceps femoris fat thickness in mm (Restriction: 6.14; Control: 5.23; Concentrate: 5.91; SEM: 0.23) compared with cattle in the control group at the end of the study. Thus, either restriction or concentrate supplementation before beginning the adaptation period to high-concentrate diets did not impact adaptation length, and both may be used as nutritional strategies to improve performance and carcass characteristics of feedlot Nellore cattle.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Purpose
The social life cycle assessment (S-LCA) methodology needs to advance in its methodological development, mainly regarding the impact assessment phase, in which a widely accepted method is ...missing. The goal of this study is to introduce a social metric to evaluate the human development of workers in production chains and economic sectors.
Methods
The applied characterization model of the proposed social metric was inspired by the Human Development Index (HDI), whose significance and wide use make it a good proxy to express human prosperity. Similar to HDI, our indicator called Workers’ Human Development Index (W-HDI) is derived from the geometric mean of the three dimensions of HDI, covering education, income, and health aspects of workers in different economic sectors linked to a given production chain. W-HDI proposal was tested by performing a case study from the sugarcane industry in Brazil, considering different sugarcane biorefinery configurations, including a couple of first-generation ethanol options and an integrated first- and second-generation ethanol production system (1G2G).
Results and discussion
The proposed metric was used to address the social impacts of different biorefinery scenarios. The scenario representing the first-generation ethanol production with basic technology achieved the lowest W-HDI score mostly because of the manual sugarcane harvesting system that contributed to a higher rate of occupational accidents (lower health dimension), fewer years of education, and lower wages than the other biorefinery scenarios. The highest W-HDI was obtained by the 1G2G scenario, mainly due to a more advanced technology reflected by the higher educational profile (more years of schooling) required to the workers and better wages. Additionally, our proposed W-HDI was applied in the assessment of Brazilian economic sectors, and most of them (84%) obtained medium or high development levels.
Conclusions
The present study contributes to the development of sustainability assessment tools by providing advances in the social life cycle assessment methodology. More specifically, the W-HDI is proposed to address the impact assessment phase with an indicator that can be applied in many sectors and production chains.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Abstract
Natural revegetation, afforestation, and lignocellulosic crops for bioenergy, possibly coupled with a developing technology like carbon capture and storage, are the most common land-based ...climate change mitigation options. However, they can compete for land and threaten food security or nature conservation. Using abandoned cropland for their deployment can minimize these risks, but associated potentials are unclear. Here, we compare alternative land-based mitigation options by integrating historical and future (up to 2050) abandoned cropland with site-specific biomass yields and life-cycle emissions. Considering natural revegetation in biodiversity priority areas and different measures in the remaining land can achieve a mitigation potential of 0.8–4.0 GtCO
2
-equivalents yr
−1
(2–11% of 2021 global CO
2
emissions). Afforestation generally provides larger climate benefits than bioenergy, but bioenergy with carbon capture and storage delivers the highest mitigation in most locations. Overall, these results offer refined estimates of mitigation potentials from abandoned cropland and highlight opportunities for context-specific mitigation measures.
The phase point operator Δ(q,p) is the quantum mechanical counterpart of the classical phase point (q,p). The discrete form of Δ(q,p) was formulated for an odd number of lattice points by Cohendet et ...al. and for an even number of lattice points by Leonhardt. Both versions have symplectic covariance, which is of fundamental importance in quantum mechanics. However, an explicit form of the projective unitary representation of the symplectic group that appears in the covariance relation is not yet known. We show in this paper the existence and uniqueness of the representation, and describe a method to construct it using the Euclidean algorithm.
One of the main objectives of the Transiting Exoplanet Survey Satellite (TESS) mission is the discovery of small rocky planets around relatively bright nearby stars. Here, we report the discovery and ...characterization of the transiting super-Earth planet orbiting LHS 1478 (TOI-1640). The star is an inactive red dwarf (
J
~ 9.6 mag and spectral type m3 V) with mass and radius estimates of 0.20 ± 0.01
M
⊙
and 0.25 ± 0.01
R
⊙
, respectively, and an effective temperature of 3381 ± 54 K. It was observed by TESS in four sectors. These data revealed a transit-like feature with a period of 1.949 days. We combined the TESS data with three ground-based transit measurements, 57 radial velocity (RV) measurements from CARMENES, and 13 RV measurements from IRD, determining that the signal is produced by a planet with a mass of 2.33
−0.20
+0.20
M
⊕
and a radius of 1.24
−0.05
+0.05
R
⊕
. The resulting bulk density of this planet is 6.67 g cm
−3
, which is consistent with a rocky planet with an Fe- and MgSiO
3
-dominated composition. Although the planet would be too hot to sustain liquid water on its surface (its equilibrium temperature is about ~595 K, suggesting aVenus-like atmosphere), spectroscopic metrics based on the capabilities of the forthcoming
James Webb
Space Telescope and the fact that the host star is rather inactive indicate that this is one of the most favorable known rocky exoplanets for atmospheric characterization.
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