The methane dry-reforming and steam reforming reactions were studied as a function of pressure (1–20 atm) at 973 K in conventional packed-bed reactors and a membrane reactors. For the dry-reforming ...reaction in a conventional reactor the production yield of hydrogen rose and then decreased with increasing pressure as a result of the reverse water-gas shift reaction in which the hydrogen reacted with the reactant CO2 to produce water. For the steam reforming reaction the production yield of hydrogen kept increasing with pressure because the forward water-gas shift reaction produced additional hydrogen by the reaction of CO with water. In the membrane reactors the methane conversion and the hydrogen production yields were higher for both the dry-reforming and steam reforming reactions, but for the dry reforming at high pressure half of the hydrogen was transformed into water. Thus, the dry-reforming reaction is not practical for producing hydrogen.
The dry reforming of methane forms substantial amounts of water at high pressure and is not a practical method for hydrogen production. CH4 + 2CO2 → H2 + H2O + 3CO. Display omitted
► The CH4 dry-reforming reaction produces H2O through the reverse water-gas shift. ► The CH4 steam reforming produces additional H2 by the forward water-gas shift. ► Membrane reactors improve the hydrogen yield for both reforming reactions. ► There is little future in the dry-reforming reaction for hydrogen production.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The micro-turbojet engine (MTE) is especially suitable for unmanned aerial vehicles (UAVs). Because the rotor speed is proportional to the thrust force, the accurate speed tracking control is ...indispensable for MTE. Thanks to its simplicity, the proportional-integral-derivative (PID) controller is commonly used for rotor speed regulation. However, the PID controller cannot guarantee superior performance over the entire operation range due to the time-variance and strong nonlinearity of MTE. The gain scheduling approach using a family of linear controllers is recognized as an efficient alternative, but such a solution heavily relies on the model sets and pre-knowledge. To tackle such challenges, a single neural adaptive PID (SNA-PID) controller is proposed herein for rotor speed control. The new controller featuring with a single-neuron network is able to adaptively tune the gains (weights) online. The simple structure of the controller reduces the computational load and facilitates the algorithm implementation on low-cost hardware. Finally, the proposed controller is validated by numerical simulations and experiments on the MTE in laboratory conditions, and the results show that the proposed controller achieves remarkable effectiveness for speed tracking control. In comparison with the PID controller, the proposed controller yields 54% and 66% reductions on static tracking error under two typical cases.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
A hydrothermally stable and H
2-selective composite membrane was successfully prepared on a mesoporous alumina support by thermal decomposition of titanium isopropoxide (TIP) and ...tetraethylorthosilicate (TEOS) at high temperature. The membrane with a H
2-selective silica–titania top layer of 10–20
nm in thickness had a H
2 permeance 3
×
10
−7
mol
m
−2
s
−1
Pa
−1 and a H
2 selectivity over CH
4 and CO
2 in the range of 40–60. After 130
h exposure in 75
mol% H
2O at 923
K, the H
2 permeance was reduced by only 30%, compared to a pure silica membrane which suffered a loss of 90%. The use of the opposing reactants technique improved the quality of the composite membrane. Although considerable more efforts are needed to increase surface area, the stability properties suggest applicability of the composition at high temperature in the presence of high concentrations of steam.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
This study was conducted to evaluate the effects of dietary squalene supplementation on the growth performance, plasma biochemical indices, antioxidant status, and meat quality in broilers. Two ...hundred and forty 0-day-old male chicks were allocated into 5 groups of 6 replicates and were fed a basal diet supplemented with 0 (Control group), 250, 500, 1,000, or 2,000 mg/kg squalene for 42 d. Dietary squalene supplementation linearly increased weight gain and feed efficiency of broilers during the grower and overall periods (P < 0.05). Squalene linearly decreased 21-d malondialdehyde (MDA) level and 42-d glutathione peroxidase (GSH-Px) activity, and both linearly and quadratically decreased 42-d MDA level in plasma (P < 0.05). In contrast, squalene linearly increased plasma reduced form of glutathione (GSH) level on 21 and 42 d and superoxide dismutase activity on 42 d (P < 0.05). Squalene supplementation linearly decreased 21-d MDA accumulation but linearly increased GSH level on 21 d and 42 d and both linearly and quadratically increased 21-d GSH-Px activity in liver (P < 0.05). Supplementing squalene linearly increased pH value at 48 h and linearly decreased lightness at 48 h and 24-h drip loss of breast muscle (P < 0.05). The lightness at 24 h and cooking loss of breast muscle were both linearly and quadratically reduced by squalene (P < 0.05). Dietary squalene administration linearly decreased MDA accumulation but linearly increased GSH level and GSH-Px activity of breast muscle (P < 0.05). Compared with the control group, aforementioned growth performance, antioxidant-related parameters (except 42-d GSH-Px in plasma and breast and hepatic GSH), and meat quality were improved by squalene when its level was 1,000 and 2,000 mg/kg (P < 0.05), with their results being similar between these 2 groups (P > 0.05). It was concluded that squalene administration especially at a level of 1,000 mg/kg can improve growth performance, antioxidant status, and meat quality in broilers, providing insights into its application as a potential feed additive in broiler production.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The motion planning and control method of automated vehicles, as the key technology of automated vehicles, directly affects the safety, comfort, and other technical indicators of vehicles. The ...planning module is responsible for generating a vehicle driving path. The control module is responsible for driving the vehicle. In this study, we review the main methods and achievements in motion planning and motion control for automated vehicles. The advantages and disadvantages of various planning and control methods are comparatively analyzed. Finally, some predictions and summaries based on the existing research results and trends are proposed. Through this analysis, it is believed that various types of algorithms will be further integrated in the future to complement each other's strengths and weaknesses. The next area of research will be to establish more accurate vehicle models to describe vehicle motion, improve the generalization-solving ability of algorithms, and enhance the planning and control of integrated 'human-vehicle-road' traffic systems.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
A thin layer (30–40
nm) of a dual-element silica–alumina composition was deposited on a porous alumina support by chemical vapor deposition (CVD) in an inert atmosphere at high temperature. Prior to ...CVD, an intermediate layer of γ-alumina was coated on the macroporous alumina support. The intermediate layer was prepared by the dip-coating and calcination of boehmite sols of different sizes to give a graded structure that was substantially free of defects. The resulting supported composite membrane had high permeance for hydrogen in the order of 2–3
×
10
−7
mol
m
−2
s
−1
Pa
−1 at 873
K with selectivities of H
2 over CH
4, CO and CO
2 of 940, 700 and 590, respectively. The membrane operated by a hopping mechanism involving jumps of permeating molecules between solubility sites. The presence of aluminum improved the hydrothermal stability of the membranes for periods in excess of 500
h at 873
K in 16% steam, allowing the permeance to remain above 10
−7
mol
m
−2
s
−1
Pa
−1, although with decreased selectivities.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Protein oxidation of soybean meal (SBM) during storage may have adverse effects on the intestinal health of laying hens. Moreover, rutin has anti-inflammatory and antioxidant properties which might ...be used as a feed additive to mitigate the intestinal damage caused by oxidised protein of SBM. This study aimed to investigate the effects of rutin supplementation on intestinal morphology, antioxidant capacity, immunity and caecal microbiota in laying hens fed a diet containing stored SBM. A total of 384 Hy-Line Brown laying hens (220 days) were randomly allocated into four groups with eight replicates of 12 laying hens each according to a 2 × 2 factorial arrangement with 2 types of SBM (FSM: SBM was stored in the cold storage warehouses at −20 °C for 45 days, and was considered as fresh and control SBM; RTSM: SBM was stored in room temperature warehouse (15 °C to 25 °C), average temperature was 20 °C for 45 days) and 2 levels of rutin (0 and 500 mg/kg). The results showed that the RTSM diet decreased the ileal glutathione peroxidase (GSH-Px) activity, the jejunal superoxide dismutase 2 (SOD2) and ileal NAD(P)H: quinone oxidoreductase 1 (NQO1) mRNA expression levels (p < 0.05), and tended to decrease the jejunal superoxide dismutase 1 (SOD1), ileal glutathione peroxidase 1 (GPX1) and increase the jejunal interleukin-1β (IL-1β) and interleukin-4 (IL-4) mRNA expression levels. Dietary rutin decreased the jejunal crypt depth (CD) (p < 0.05), increased the jejunal total antioxidant capacity (T-AOC) and GSH-Px activities (p < 0.05), decreased the content of interferon-γ (IFN-γ) in the jejunum (p < 0.05), and significantly reduced levels of immunoglobulin G (IgG), IL-1β, tumour necrosis factor-α (TNF-α), IFN-γ, and IL-4 in the ileal mucosa (p < 0.05). Dietary rutin increased SOD2, nuclear factor E2-related factor 2 (Nrf2) and NQO1 mRNA expression levels in the jejunum and GPX1, Nrf2 and NQO1 mRNA expression levels in the ileum, and decreased nuclear factor-κB (NF-κB), IL-1β, IFN-γ and IL-4 mRNA expression in the jejunum and NF-κB, IL-1β, TNF-α, IFN-γ and IL-4 mRNA expressions in the ileum. What’s more, dietary rutin changed the caecal microbiota. PCoA analysis indicated significant structural differences among four groups (p < 0.05), and SBM × Rutin interactions were found in Actinobacteriota and unclassifiedk_norank_d_ Bacteria at the phylum level (p < 0.05). These results suggested that RTSM had slight adverse effects on the intestinal health, and dietary rutin improved intestinal morphology, exerted antioxidant and anti-inflammatory effects via Nrf2 and NF-κB signal pathways, and changed the composition of caecal microbiota.HighlightsThe RTSM diet has adverse effects on the intestinal health of laying hens compared with the FSM diet.Dietary rutin improved the intestinal health by increasing the intestinal morphology, antioxidant capacity and anti-inflammatory effects.Dietary soybean meal and rutin changed the composition of caecal microbiota.
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The vapor-phase epoxidation of propylene with H2 and O2 over a highly dispersed Au/TS-1 catalyst was carried out in a packed-bed catalytic membrane reactor. The membrane reactor allowed the use of ...high concentrations of H2 and O2 (40% each) that were well within the explosive regime, and the production rate of propylene oxide was improved by 100-200% compared with that from a conventional packed-bed reactor. At 180 degrees C, the C3H6 conversion was 10% and the PO selectivity was 80%, corresponding to a space-time yield of formula omitted, whereas at 212 degrees C, the yield increased to formula omitted. The kinetic dependency, rPO=k (H2)0.53 (O2)0.26 (C3H6)0.18, obtained free from mass transport and heat transfer limitations at these high concentrations was in good agreement with that reported at low concentrations. PUBLICATION ABSTRACT
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
This study aimed to investigate the effects of rutin on laying performance, egg quality, serum biochemical parameters, serum immunoglobulin, and antioxidant status in laying hens fed a diet ...containing stored soybean meal (SBM). The dietary treatments used were arranged in a 2 × 2 factorial arrangement with 2 types of SBM (FSM: SBM was stored in the cold storage warehouses at −20 °C for 45 days and was considered as fresh SBM; RTSM: SBM was stored in room temperature warehouse (15 °C to 25 °C), average temperature was 20 °C for 45 days) and 2 levels of rutin (0 and 500 mg/kg). In total, 384 Hy-Line Brown laying hens (220 days of age) were randomly divided into 4 groups with eight replicates. Pre-feeding period was 1 week, and the experiment lasted for 8 weeks. The results showed that the RTSM diet had no effect on laying performance (p > 0.05). Compared with the diet without rutin, diet with 500 mg/kg rutin exhibited a tendency to increase egg mass compared with the diet without rutin (p = 0.096), and there was a trend of interaction effect on average egg weight (p = 0.061). The RTSM diet decreased the egg Haugh unit significantly compared with the FSM diet at the end of 8th week (p < 0.05). Compared with the diet without rutin, dietary rutin supplementation could affect egg quality as evidenced by increased eggshell thickness, albumen height, egg yolk colour at the end of 4th week and increased eggshell strength and eggshell thickness at the end of 8th week (p < 0.05). Furthermore, dietary rutin supplementation increased urea nitrogen, decreased the immunoglobulin M (IgM) content in serum compared with the diet without rutin (p < 0.05). Compared with the diet without rutin, dietary supplementation with rutin improved the total antioxidant capacity in the serum and liver (p < 0.05). The interactions of SBM × Rutin were observed on egg yolk ratio at the end of 8th week, and the urea nitrogen and IgM content in serum. These findings suggested that diet with RTSM had adverse effects on egg quality in laying hens. The RTSM diet negatively impacted egg quality of laying hens over time when compared to the FSM diet. Dietary rutin supplementation could improve the egg quality, and antioxidant capacity of laying hens.
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The multi-terminal systems can be used as basic building blocks of nanoelectronic devices. However, the understanding of mode-dependent phonon transmission in these systems remains poorly developed. ...Hence, we examine the modal transmission processes for a T-shaped three-terminal structure, which has one zigzag graphene nanoribbon (GNR) vertically joined together with an armchair GNR as the side terminal. The atomistic Green’s function method is improved to be suitable for exploring the polarized phonon transmittance between terminals in the multi-terminal system, by treating the terminals in a uniform and standard way. Initially propagating along a zigzag GNR, the phonons turn 90° to the side terminal, or go straight ahead. The change of transport direction to the side terminal leads to a relatively low transmittance in most cases. However, the acoustic phonon transmittance spectrum has alternating prominent dips and sharp peaks, and can have a higher value even with the abrupt direction changing in some frequency ranges. Along the zigzag GNR, most of acoustic phonons do not change polarization mode after scattering. However, most of low frequency longitudinal (LA), transverse (TA), flexural (ZA) and rotational (ZA4) acoustic phonons convert into TA, LA, ZA4 and ZA phonons in the side terminal, respectively.
Display omitted
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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