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Ligand binding and partial characterization of sex-specifically expressed lipocalins of submandibular and lacrimal glands of Syrian hamsters
Human adaptation to adaptive machines converges to game-theoretic equilibria
A high-entropy image encryption scheme using optimized chaotic maps with Josephus permutation strategy
Androgen receptor signaling induces hemorrhage and angiogenesis in the irradiated bladder
Selective deletion or preservation of tissue components via enzymatic digestion monitored by scanning acoustic microscopy
Analysis of deformation rule of deep foundation pit excavation of railway station in soft soil with silt
Targeting oncofetal fibronectin and neuropilin-1 in solid tumors with PL2 peptide
Optimizing hybrid network topologies in communication networks through irregularity strength
Half-thickness discretized format for simulating compressible delay interbed
Abstract The simulation of compressible delay interbed is an important component of ground subsidence modeling. Currently, the most widely used groundwater simulation software, MODFLOW, has two modules: SUB and CSUB. While both can simulate compressible delay interbed using the one-dimensional head diffusion equation, they differ in approach. The SUB module relies on the principle of head change, while the CSUB module is based on the principle of geostress variation, addressing the shortcomings of the SUB module when simulating ground subsidence in unconfined aquifers. When based on the principle of head change, the effective stress acting on the top and bottom of the interbed is the same, leading to symmetric vertical consolidation and using half-thickness discretization. In contrast, the CSUB module is based on geostress variation, the effective stress acting on the top and bottom of the interbed is not the same, which results in asymmetric consolidation and requires full-thickness discretization. With the same vertical discretization interval for the compressible delay interbed, the computational workload and memory requirements are approximately twice that of the SUB module. Based on the characteristic of linear distribution of geostress in the vertical direction of the compressible delay interbed, this paper proposes a half-thickness discretization format under the principle of geostress variation, which can significantly improve simulation efficiency and reduce memory requirements. To validate this approach, three cases were tested with different numbers of discretization units, different interbed thicknesses, different heads, and different vertical hydraulic conductivities. A comprehensive comparison was made between the half-thickness discretization format and the full-thickness discretization format of the CSUB module. The differences in computation time and memory usage between the two methods were then analyzed. The results show that the maximum difference in the interbed water release between the half-thickness method and the CSUB module is less than 0.4%, indicating good accuracy. Additionally, the half-thickness method reduced computation time by 46.2303% and memory usage by 13.6364% in the tested cases, demonstrating significant computational advantages. This study provides an efficient and feasible technical approach for large-scale, high-precision land subsidence modeling.
Markov analysis and the Langevin equation of the Earth surface temperature data
Discovery of Streptomyces marinisediminis sp. nov., a new thiolutin producing actinomycete isolated from Thai marine sediment
Design and fabrication of 4 double input NAND gate chip with excellent electrical and physical performances
Abstract In order to improve the performances of 4 two-input NAND so that it can be better used in the aerospace application field and in harsh environments, 4 two-input NAND gate chips were designed and successfully fabricated in this paper, based on 1.2 $${\upmu }$$ m P-well SPDM CMOS technological processes. The N transistors were fabricated in P-well and connected to GND via $$P^+$$ -well. The metal wires of $$V_{CC}$$ use $$N^+$$ substrate to contact $$V_{CC}$$ , to increase its anti-locking capability. An ESD protection circuit was designed at the input terminals, prohibiting the terminal of IC chip from being damaged by ESD stress. The performance of the device is superior to that of other similar products in the world.
How Indigenous values permeate my chemistry teaching and research
Effects of permeability, grid resolution, and carbonate reactions on CO2 distribution and sulphate scaling in seawater-flooded carbonates
Abstract During oilfield production, mineral scale deposition in production wells and surface facilities presents major difficulties, particularly when water breakthrough occurs. Hard sulphate scales, like barite, are frequently the result of incompatible interactions between the formation and injection waters. In contrast, carbonate scales are caused by variations in the temperature, pressure, pH, composition of the brine, and the amounts of CO2 in the aqueous and hydrocarbon phases. In waterflooded reservoirs where injection water composition can be controlled, this study investigates the effects of temperature, ionic concentration, pH, and CO2 availability on the risks of carbonate and sulphate scaling. Particularly, scaling hazards in carbonate-rich formations are greatly influenced by precipitation of magnesium-rich carbonate. The significance that CO2 partitioning from hydrocarbons into injected saltwater plays in scaling estimates has been ignored in earlier studies. To close this gap, this study investigates how temperature and reservoir pressure affect oil recovery and scale management, particularly in systems that dip below bubble point pressure. A commercial reservoir simulator, which couples aqueous and mineral geochemistry with three-phase fluid flow calculations, has been used in this study. Equilibrium reactions have been considered in three-dimensional (3D) models. Oilfield data have been used to identify the parameters of significance to consider in the calculations, such as ionic concentrations, hydrocarbon composition, mineral components etc. Key findings, importantly, the results identify that for the reservoir temperature of 100 °C considered and for the primary mineral assemblage, calcite dissolution and magnesium-rich carbonate precipitation are interdependent. They are affected by the abundance of CO2 in the residual oil phase, and this evolves over time, impacting the concentration of calcium and magnesium in the brines traversing the reservoir. Temperature changes around the injection wellbore also impact component and mineral solubilities, especially in terms of anhydrite and gypsum reactions. All these factors impact the calcium, magnesium, barium, strontium, sulphate and bicarbonate concentrations at the production well, and hence the scaling risk in the production system. In conclusion, managing reservoir conditions such as temperature, ionic concentrations, and CO2 distribution is important for reducing the likelihood of scale deposition while preserving oil recovery in carbonate-rich, water-flooded reservoirs.
Transient oxidation of hazes a source of nutrients during the great oxidation event
Abstract The transition period of the Great Oxidation Event (GOE) saw the emergence of transient physical and chemical processes. In this context, photochemical organic hazes may have evolved in an atmosphere containing low concentrations of oxygen (< 10− 5/10− 6 Present Atmospheric Level). This coexistence of organic aerosols and oxygen traces induced an atmospheric reactivity which has so far been unexplored. Here, we show that the progressive rise of oxygen around the GOE triggered oxidation of organic aerosols suspected to be present at that time. We estimate that such transient mechanisms would have persisted over 60 to 100 Myrs during the GOE and possibly extended during the Archean. The main chemical markers of aerosol oxidation observed are urea, oxalic acid and carboxylic acid derivatives. These oxygen-bearing organics identified could have served as nutrients by existing ecosystems. This input of oxidized organic matter, estimated between 1013 and 1015 g of C.yr− 1 based on aerosol production yields, has probably been significant compared to oxygenic photosynthesis. Such mechanisms could also have diversified the pool of available nutrients, constituting an interesting vector of biodiversity for the primitive ecosystem.