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Enhancing safflower traits: a comparative study of fertilizer treatments on growth, yield, and oil quality
No full textEfficient nutrient management plays a key role in improving safflower (Carthamus tinctorius L.) yield and oil quality. This study examined the effects of conventional and integrated fertilization strategies on safflower growth, yield components, oil yield, and fatty acid composition over two growing seasons (2021–2023) in Tabriz, Iran. A randomized complete block design included six treatments: an unfertilized control, 100% urea (UR), foliar NPK, and the biofertilizer PhosphoBARVAR-2 (PSB) combined with 100% UR, 50% UR, or NPK. All fertilized treatments performed significantly better than the control in most parameters across both years. The chlorophyll index increased by up to 31.12% under PSB+100% UR in Year 2 and by 38.43% under NPK in Year 1, showing improved photosynthetic activity. Seed yield rose markedly, reaching 296.18 g/m2 with NPK in Year 1 and 290.78 g/m2 with PSB+NPK in Year 2. Oil yield also increased sharply by 66.2% with NPK in Year 1 and 58.87% with PSB+NPK in Year 2 compared to the control. The highest oil content (37.7%) was recorded with PSB+50% UR. Integrated nutrient management (INM) treatments, i.e., PSB+100% UR, PSB+50% UR, and PSB+NPK, proved highly effective. They often matched or exceeded the performance of full conventional fertilization, particularly PSB+50% UR. These treatments also enhanced oil composition. PSB+100% UR and PSB+50% UR produced the highest linoleic acid (C18:2) levels (up to 73.55%), while PSB+NPK maximized the amount of oleic acid (C18:1) to 16.05% and total unsaturated fatty acids to 83.57%. Cluster analysis clearly separated INM treatments, highlighting their distinct impact. Overall, integrating PSB with urea or NPK fertilizers, even at reduced rates, offers a promising and sustainable approach to improve both safflower yield and oil quality
Retrofitting aged masonry buildings using advanced cementitious fibre reinforced concrete material: case study and comparison to traditional methods
No full textChina has a large stock of existing aged buildings that can no longer meet the needs of modern life and need to be reinforced to improve their seismic resistance. Complete demolishing and rebuilding waste resources while retrofitting and reusing are more sustainable. However, residents feel reluctant to invest in retrofitting their dwellings, even with government funding, because of its high cost. Previous research has mainly focused on upgrading heating, ventilation, air conditioning (HVAC), and lighting to benefit from energy-saving and carbon emission reduction without considering holistic renovation requirements. On the other hand, traditional retrofitting techniques were widely reported in the literature worldwide to improve structural integrity, load-bearing capacity, and seismic performance. However, little research has been conducted on the cost-effectiveness of different retrofitting methods, especially the emerging methods involving more advanced construction materials, such as highly ductile fibre-reinforced concrete (HDC). To fill this gap, this study compared two retrofitting plans for an aged masonry building. Satisfying various renovation requirements, the retrofitting plan utilising HDC led to a nearly 32% reduction in cost and approximately 36% reduction in construction time when compared to traditional renovation methods. The building information modelling (BIM) tools helped calculate quantities and improve stakeholder communication efficiency
DIII-D High Field Side Lower Hybrid Current Drive Experiment Overview
No full textIn preparation for high field side lower hybrid current drive (HFS LHCD) experiments in DIII-D, the HFS LHCD was to be commissioned and physics experiments commence once the system operated up to 300 kW for 0.5 s. The initial physics experiments sought to characterize coupling, wave propagation, and driven current measurements. In HFS LHCD first campaign, the maximum power was limited to <200 kW due to waveguide pressure leaks limiting the number of available modules and power per module. Here we summarize commissioning progress and initial physics observations. The HFS LHCD coupler was optimized for high qmin, DIII-D discharges where efficient off-axis current at r/a~0.6-0.8 is desired. The coupler n|| spectrum is peaked at 2.7 and is predicted to generate ~0.14 MA/MW coupled for 1.6 MW injected. In preparation, the HFS scrape-off layer density profile was characterized and found to have steeper profiles and lower fluctuation levels than the low field side. Furthermore, the HFS SOL density profile can be accurately predicted using global plasma quantities using machine learning. Thus far, one module has injected ~100 kW for 0.5 s with <5% reflected power. Nonthermal electrons have been observed on lower frequency channels of the electron cyclotron emission radiometer correlated with the LH power indicating core wave absorption. To avoid 30R neutral beam heat flux, a split launcher is proposed to avoid the high heat flux region while maintaining power spectrum and directivity
Analysis of Parametric Decay Instabilities Driven by Helicon Waves in Tokamak Experiments
No full textIn this study, we analyse and compute the local growth rate of parametric decay instabilities of helicon waves under typical scrape-off layer conditions. Our findings are consistent with previous work [Porkolab et al., AIP Conference Proceedings 2984, 070004 (2023)], confirming that the dominant decay channels are ion cyclotron quasi-modes and their harmonics. While the parametric instability can be excited at extremely low input power, it can be suppressed by a higher electron temperature. Conversely, higher plasma densities increase the local growth rate, suggesting that helicon waves may face challenges in high-density plasmas
Bar evolution in edge-on galaxies: A demographic study of boxy/peanut bulges
No full textContext. Boxy/peanut and X-shaped (BP/X) bulges are prominent features in edge-on disk galaxies and they are believed to represent vertically thickened bars. Despite their relevance in bar evolution, a statistically robust census of these structures in large surveys remains lacking.
Aims. We aim to provide the largest catalog of BP/X structures in edge-on galaxies to date, along with an investigation of their properties and role in shaping galaxy scaling relations.
Methods. We selected a sample of 6684 edge-on galaxies from SDSS DR8 using Galaxy Zoo classifications, requiring a high edge-on probability (> 0.9) and a minimum of ten independent votes. We performed a two-dimensional (2D) image decomposition using GALFI
Lithium abundance and stellar rotation in the Galactic halo and thick disc
No full textThe stellar evolution of lithium-rich (Li-rich) giant stars at very low metallicities remains largely unexplored to date. Using mainly two recent large LAMOST catalogues of field, low-mass giant stars (both Li-rich and Li-poor) with metallicities ranging from −4.0 up to −1.0, we studied some of the conditions for Li enrichment and the general distribution of stellar rotations in the Galactic halo and thick disc. Due to the scarcity of stars with [Fe/H] −2.5. Among these stars, we detected the presence of IR excesses that are considered to be indicative of giant stars losing mass, showing a recent episodic Li-enrichment process related to the Cameron-Fowler mechanism for the formation of new 7Li. Because stars presenting IR excesses are distributed across the majority of metallicity values, we suggest this mechanism is at work throughout an important part of the evolutionary history of the Galaxy. Based on these IR excesses, we identified three Li thresholds: ∼1.5 dex for RGB stars, ∼0.5 dex for HB stars, and approximately −0.5 dex for AGB stars, thereby establishing a new criterion to characterise Li-rich giants in the halo and thick disc. We carried out a first extensive study of stellar rotations in metal-poor giant stars, revealing the following results: (a) a plateau appears for velocities greater than 40 km s−1 extending up to near 90 km s−1, with Li abundances ranging from 1.02 to 1.82 dex; (b) among Li-rich giant stars with v sin i > 40 km s−1, a clear trend toward increasing rotation is observed up to near 90 km s−1, as metallicities decrease from −1.0 to −2.5, it is observed; (c) the presence of RGB and HB Li-rich giant stars with rotations up to 90 km s−1 suggests that internal stellar models must account for extended 3He reservoir lifetimes as a source of 7Li considering these velocities. The velocity around 40 km s−1 appears to be a new critical value that merits further investigation
Research on the Performance of Concrete Anti-Segregation Agent
No full textThrough tests on the workability of concrete, setting time and compressive strength of different anti-segregation raw materials, B1 was selected as the anti-segregation raw material.Then, a series of anti- segregation agents were compounded by blending B1 with cement and mineral powder in certain proportions respectively. The effects of the anti-segregation agents on the workability, setting time and compressive strength of concrete were studied.The results show that after adding anti-segregation agents J2, J3 and J4 to the segregated concrete, compared with the blank concrete, the cohesion of the concrete is improved, the workability is enhanced, the effect on the setting time is minimal, and the 28-day compressive strength of the concrete can be increased
Construction risk evaluation of pipe jacking method in subway tunnel based on projection pursuit method
No full textThe pipe jacking for subway tunnel construction effectively minimizes impacts on urban environment, traffic and facilities, and reduces noise. However, it alters stratum stress and causes soil loss, potentially leading to tunnel collapse and surface settlement with high construction risks. To predict risks, they are classified into four levels: Ⅰ (no risk), Ⅱ (low risk), Ⅲ (high risk), Ⅳ (very high surface settlement risk). A risk evaluation index system considering engineering geology and construction factors is established. Using projection pursuit method, the optimal projection direction a=[0.345,0.425,0.285,0.225,0.235,0.245,0.395,0.544] (as index weights) is obtained via accelerated genetic algorithm, forming the risk evaluation model. Results show construction factors have greater weights than engineering geology among primary indices; top three secondary indices are construction downtime, soil conditions, and axis deviation. This indicates reasonable construction is crucial, good geology aids safety, and surface settlement risk is high during construction. The early warning results align with on-site conditions, verifying the model’s effectiveness
Study on the Adsorption Mechanism of Cu
No full textIn this study, corn straw biochar (BC) was employed as a base material, and sodium alginate (SA) was utilized as an immobilization carrier to successfully prepare sodium alginate-loaded biochar composite gel beads (SA-BC) for adsorbing Cu2+ in the solution. The bead-shaped structure of this composite offers excellent stability and reusability, making it suitable for continuous-flow column operations and practical wastewater treatment applications. The results revealed that the incorporation of sodium alginate formed a dense coating layer and a porous network that enhanced the stability and adsorption performance of the material. Kinetic analyses revealed that Cu2+ uptake by SA-BC was best described by a pseudo-second- order model, suggesting that the adsorption proceeded mainly through chemisorptive interactions. The material achieved a maximum adsorption capacity of approximately 140.66 mg·g-1. FTIR analysis further confirmed that the adsorption of Cu2+ primarily relied on the coordination interactions of carboxyl and hydroxyl functional groups. Overall, the composite material exhibits excellent adsorption capacity, operational convenience, and environmental friendliness, providing a promising and sustainable approach for the removal of heavy metal pollutants
A general maximum principle for partially observed stochastic evolution control systems
No full textIn this paper, we study an optimal control problem of partially observed stochastic evolution equation control system. The observation process is an infinite-dimensional stochastic process, and the control variable is allowed to enter the diffusion term of the state process and the drift term of the observation process. The control domain need not be convex. Combined with Girsanov theorem, we establish the related stochastic maximum principle in the sense of transposition solution