Equilibrium Model Research Articles

Modulating self-assembly and polymorph transitions in bisdendronized squaramides

Supramolecular self-assembly is an advanced approach for constructing ordered nanoscale architectures with broad applications. While the principles of supramolecular polymerization have been thoroughly explored in artificial small molecules, polymer transformations remain barely explored, likely due to the lack of suitable reference models presenting well-defined and reversible transitions between aggregates. In this study, we introduce a series of bisdendronized squaramides (SQs) 1-3, showcasing complex self-assembly behaviours involving four distinct aggregates, three different interaction patterns, and various thermodynamically controlled polymorph transformations. Notably, SQ 3, with ethyl spacers between the SQ cores and the dendrons, exhibits a concentration and temperature-dependent equilibrium among three polymorphs: the particle-like Agg-A and fibrillar Agg-C, formed by slipped hydrogen bonds, and the fibrillar Agg-B, formed by head-to-tail hydrogen bonds. Additional solid-state experiments revealed that these SQs also form columnar liquid crystals, assembled by π–π interactions in SQ 1 and hydrogen bonding in SQ 2 and SQ 3. This work positions SQ units as valuable models for understanding polymorph equilibrium in solution and solid-state, which is crucial for developing stimuli-responsive supramolecular polymers.

Understanding Uncertainty in Market-Mediated Responses to US Oilseed Biodiesel Demand: Sensitivity of ILUC Emission Estimates to GLOBIOM Parametric Uncertainty.

The life cycle greenhouse gas (GHG) emissions of biofuels depend on uncertain estimates of induced land use change (ILUC) and subsequent emissions from carbon stock changes. Demand for oilseed-based biofuels is associated with particularly complex market and supply chain dynamics, which must be considered. Using the global partial equilibrium model GLOBIOM, this study explores the uncertainty in market-mediated impacts and ILUC-related emissions from increasing demand for soybean biodiesel in the United States in the period 2020-2050. A one-at-a-time (OAT) analysis and a Monte Carlo (MC) analysis are performed to assess the sensitivity of modeled ILUC-GHG emissions intensities (gCO2e/MJ) to varying key economic and biophysical model parameters. Additionally, the influence of the approach on the simulation of future ILUC effects is explored using two alternative ILUC-GHG metrics: a comparative-static approach for 2030 and a recursive-dynamic approach using model outputs through 2050. We find that projected ILUC-GHG values largely vary based on which vegetable oils replace diverted soybean oil, market responses to coproducts, and the carbon content of land converted for agricultural use. These are all, in turn, subject to decision uncertainty through the choice of the modeling approach and the time horizon considered for each ILUC-GHG metric. Given the longer simulation period, ILUC-GHG emission uncertainty ranges increase under the recursive-dynamic approach (42.4 ± 25.9 gCO2e/MJ) compared to the comparative-static approach (40.8 ± 20.5 gCO2e/MJ). The combination of MC analysis with other techniques such as Bayesian Additive Regression Trees (BART) is powerful for understanding model behavior and clarifying the sensitivity of market responses, ILUC, and associated GHG emissions to specific model parameters when simulated with global economic models. The BART reveals that biophysical parameters generate more linear ILUC-GHG responses to changes in assumed parameter values while changes in economic parameters lead to more nonlinear ILUC-GHG results as multiple effects at the interplay of food, feed, and fuel uses overlap. The choice of the recursive-dynamic metric allows capturing the longer-term evolution of ILUC while generating additional uncertainties derived from the baseline definition.

Higher education expansion and emission trading scheme: A case study in China.

Despite the abundant empirical evidence of higher education impacting emission mitigation, few studies have uncovered the mechanism that higher education affects climate policy. In this paper, we attempt to narrow the aforementioned research gap by employing a Computable General Equilibrium (CGE) model to quantify the relations between the higher education expansion (HEE) and emission trading scheme (ETS) in China. The CGE model results show that the HEE reduces labor employment, GDP, and emissions, whereas the ETS relieves these HEE impacts. Regardless of the HEE, the ETS causes emission abatement at the price of employment loss and GDP loss, whereas the HEE weakens the ETS effects on employment, GDP, and emissions. These findings imply that HEE negatively affects emission mitigation in climate policy implementation, whereas climate policy could be implemented to boost economic growth during college education expansion.

Dynamic light field reconstruction via densely connected deep equilibrium model

High-resolution consumer plenoptic cameras usually feature low frame rates, making them not well-suited for capturing high-speed motion scenes. To compensate for this limitation, we extend the original snapshot compressive imaging system to plenoptic cameras and propose a densely connected deep equilibrium (DEQ) model for high-quality dynamic light field (LF) reconstruction, abbreviated as DLFDEQ. Specifically, we perform temporal compression encoding on a dynamic LF and model the reconstruction process as an inverse problem with an implicit regularization term. To solve this inverse problem, we present a densely connected DEQ model based on gradient descent. Our approach demonstrates stronger robustness and better detail retention than existing methods. We can practically quadruple the original camera’s frame rate by continually capturing and retrieving these measurement frames with high reconstruction accuracy.

Impacts of Re-export Demand on Benin’s Economy

This article analyses the impact of re-export demand on the Beninese economy. Re-export is dominant in Benin’s trade and may represent risks to the economy’s vulnerability. The methodology uses a dynamic computable general equilibrium model. It simulates two scenarios: the first considers a one-off decline in re-export demand in the first year, while the second analyses the impact of a recurring annual shock. The results, both at the aggregate and sectoral levels, indicate that the decline in re-export demand would negatively affect real GDP, domestic and net external demand, and most industries. This article extends the existing knowledge on the re-export phenomenon by adding a dynamic analysis of its potential impact at the aggregate and sectoral levels. The results confirm that re-export is a source of vulnerability for the Beninese economy. The authorities should focus on diversifying the economy and strengthening the competitiveness of the Port of Cotonou, in order to mitigate vulnerabilities linked to re-export activities. JEL Codes: C68, F17

Teaching the Job Guarantee with Keynes’ Z-D diagram

The Job Guarantee may well be the only policy tool capable of addressing the myriad serious and sometimes existential problems we face today. Fortunately, it can be added ad hoc to even Orthodox economics courses so long as the possibility of less-than-full employment is admitted. Unfortunately, such an inherently incompatible framework greatly reduces the likelihood that the student remembers the lesson beyond the final exam. In almost every program, they will have been exposed to Neoclassicism’s arsenal of self-reinforcing and mutually-consistent free-market analogies and metaphors, leading them to–if not the day of the lecture, then as time passes–view the Job Guarantee as a curious outlier. This is why placing it in the context of Keynes’ Z-D diagram is so important. Because it is a general equilibrium model whose two main components are drawn straight from the mainstream tradition, it will feel familiar to Neoclassically-trained students. And yet it is that very familiarity that creates the opportunity for an epiphany. With a few intuitively-appealing modifications to the mainstream story, they will not only come to learn how powerful the Job Guarantee can be, but they may actually remember it.

The Conversion of Ethanol to Syngas by Partial Oxidation in a Non-Premixed Moving Bed Reactor

An experimental investigation into the conversion of ethanol to syngas by partial oxidation in a non-premixed counterflow moving bed filtration combustion reactor was carried out. Regimes of conversion depending on the mass flow rates of fuel and air (separate feeding), as well as a granular solid heat carrier, were studied. Depending on the mass flow rate of the heat carrier, two combustion modes were realized—reaction trailing and intermediate—with different temperature patterns in the gas preheating, combustion, and cooling zones along the reactor. The product gas composition is far from the predictions of the equilibrium model; it contains substation fractions of methane and ethylene. Combustion temperature and conversion are limited by the relatively high level of heat loss from the laboratory-scale reactor. The effect of the heat loss can be reduced by enhancing the absolute flow rate of the reactants.

Fe2O3/polypyrrole/peanut husk composite for the adsorptive removal of Basic Blue 41 from the aqueous medium: Kinetics, equilibrium modeling and thermodynamic studies

In this study, Basic Blue 41 (BB41) was adsorbed from an aqueous medium using a peanut husk (PH) functional composite with polypyrrole/Fe3O4. For the adsorption of BB41 dye, the effects of process variables including pH, sorbent dose, dye concentration, agitation time, and temperature were investigated. The magnetic composite showed the highest efficiency for the adsorbents at pH 7-10, 0.05 g adsorbent dose, 90 min contact time and 200 mg/L initial dye concentration at 27 °C. The qe was found up to 48 mg/g with percentage removal of up to 96% for BB41 dye for the composite. On the experimental data of BB41 dye, the Langmuir, Freundlich, Temkin, Harkin-Jura, and Dubinin-Radushkevich isotherms were applied. The BB41 adsorption data were also subjected to pseudo-first order, pseudo-second order, and intraparticle diffusion kinetic models. Thermodynamic factors, such as the change in enthalpy (ΔH°), entropy (ΔS°), and Gibbs free energy (ΔG°), were also calculated. The results show that the BB41 adsorption process is exothermic and spontaneous. Techniques such as FT-IR and scanning electron microscopy (SEM) were used to characterize the composite materials. This study demonstrated the promising adsorption potential of magnetic/polypyrrole/peanut husk composites. This class of adsorbent could be used to remediate wastewater that contains dyes.

Absorption and diffusion process at the CO[formula omitted]-decane interface considering density fluctuations near the critical CO[formula omitted] point

The injection of CO2 into geological formations for storage and for efficiency enhancement of oil production is considered a promising technology. Fundamental is an understanding of the absorption and diffusion process at the CO2-decane interface and its pressure and temperature dependence when approaching the critical CO2 point (31 °C, 7.38 MPa).Based on a new conceptual model, which considers CO2 density fluctuations in the critical range, we were able to consistently explain the time dependence of the volume increase for the respective thermodynamic state. The experimental results confirm the new conceptual model that volume swelling in the non-critical pressure range (< 6 MPa) is a surface effect with limited penetration depth. In contrast, the volume increase in the critical pressure range (6 - 8 MPa) is caused by mixing of liquid CO2droplets and the oil phase, i.e. to a level increase of the liquid mixed phase. Our experimental contact angles confirm this. The measured minimum miscible pressures (MMP) are 5.6 and 6.5 MPa at 20 °C and 30 °C, respectively.The CO2 absorption process at the CO2-decane interface is studied independently with pressure decay experiments. Our model results show excellent agreement (relative error ≅ 1 %) with the experimental results for both the non-equilibrium and equilibrium model, and the early-time diffusion coefficient is 4.7±1.9×10−7m2/s, confirming a fast CO2 mass transfer process.

X-Ray Spectroscopy of the Dwarf Nova Z Chamaeleontis in Quiescence and Outburst Using the XMM-Newton Observatory

We present X-ray spectroscopy of the SU UMa–type dwarf nova Z Chamaeleontis using the European Photon Imaging Camera and reflection grating spectrometer (RGS) instruments on board the XMM-Newton observatory. The quiescent system can be modeled by collisional equilibrium (CIE) or nonequilibrium plasma models, yielding a kT of 8.2–13.0 keV at a luminosity of (5.0–6.0) × 1030 erg s−1. The spectra yield better χν2 using partially covering absorbers of cold and/or photoionized nature. The ionized absorber has an equivalent N H = (3.4–5.9) × 1022 cm−2 and a log(ξ) = 3.5–3.7 with a (50–60)% covering fraction when the VNEI model (XSPEC) is used. The line diagnosis in quiescence shows no resonance lines, with only the forbidden lines of Ne, Mg, and Si detected. The H-like C, O, Ne, and Mg are detected. The strongest line is O viii, with (2.7–4.6) × 10−14 erg s−1 cm−2. The quiescent X-ray-emitting plasma is not collisional and not in ionization equilibrium, which is consistent with hot ADAF-like accretion flows. The line diagnosis in the outburst shows He-like O and Ne, with intercombination lines being the strongest, along with weaker resonance lines. This indicates the plasma is more collisional and denser, but not yet in CIE, revealing ionization timescales of (0.97–1.4) × 1011 s cm−3. The R ratios in the outburst yield electron densities of (7–90) × 1011 cm−3 and the G ratios yield electron temperatures of (2–3) × 106 K. The outburst luminosity is (1.4–2.5) × 1030 erg s−1. The flow is inhomogeneous in density. All detected lines are narrow, with widths limited by the resolution of RGS, yielding Keplerian rotational velocities <1000 km s−1. This is too low for boundary layers, consistent with the nature of ADAF-like hot flows.

Numerical simulation and energy consumption analysis of ventilation patterns in grain silo

Mechanical ventilation is an effective method to ensure the security of grain storage, which directly impacts the storage duration and storage quality. In this work, considering the coupling effect of grain physical parameters and gas-solid phase interaction on ventilation, the porous media, non-thermal equilibrium and turbulence models were employed to investigate the variation of velocity field and temperature field under four ventilation patterns: vertical ventilation duct (VD), transverse ventilation duct (HD), combined roof inhalation duct (CRD), and combined bottom inhalation duct (CBD). The relative standard deviation (RSD) and unit energy consumption were used to evaluate the performance of different ventilation patterns quantitatively. The results show a relative deviation of 5.12 % between simulation and experiments. Compared with VD and HD, CRD and CBD exhibit higher velocity values and gradient in the center of grain silo. The physical parameters of grain have obvious impacts on velocity field, and paddy has the highest velocity values due to its higher porosity. CRD has a significant advantage in cooling speed and effect, with the grain surface temperature at 12 m and 25 m lower than other patterns by 1.2 °C and 1.8 °C, respectively. The large porosity of paddy can advance cooling time by up to 5–10 h, while the lower specific heat capacity and higher thermal conductivity of peanut result in cooling temperatures 1.5 °C–2.4 °C lower than other grain. The temperature RSD of VD is lower than other ventilation patterns, and the unit energy consumption of CRD and CBD is better.

The Featherweight Giant: Unraveling the Atmosphere of a 17 Myr Planet with JWST

The characterization of young planets (<300 Myr) is pivotal for understanding planet formation and evolution. We present the 3–5 μm transmission spectrum of the 17 Myr, Jupiter-size (R ∼10R ⊕) planet, HIP 67522b, observed with JWST NIRSpec/G395H. To check for spot contamination, we obtain a simultaneous g-band transit with the Southern Astrophysical Research Telescope. The spectrum exhibits absorption features 30%–50% deeper than the overall depth, far larger than expected from an equivalent mature planet, and suggests that HIP 67522b’s mass is <20 M ⊕ irrespective of cloud cover and stellar contamination. A Bayesian retrieval analysis returns a mass constraint of 13.8 ± 1.0 M ⊕. This challenges the previous classification of HIP 67522b as a hot Jupiter and instead, positions it as a precursor to the more common sub-Neptunes. With a density of <0.10 g cm−3, HIP 67522 b is one of the lowest-density planets known. We find strong absorption from H2O and CO2 (≥7σ), a modest detection of CO (3.5σ), and weak detections of H2S and SO2 (≃2σ). Comparisons with radiative-convective equilibrium models suggest supersolar atmospheric metallicities and solar-to-subsolar C/O ratios, with photochemistry further constraining the inferred atmospheric metallicity to 3 × 10 solar due to the amplitude of the SO2 feature. These results point to the formation of HIP 67522b beyond the water snowline, where its envelope was polluted by icy pebbles and planetesimals. The planet is likely experiencing substantial mass loss (0.01–0.03 M ⊕ Myr−1), sufficient for envelope destruction within a gigayear. This highlights the dramatic evolution occurring within the first 100 Myr of its existence.

Market-oriented reforms and wealth inequality in China

Over the last few decades, China’s growing wealth inequality has mirrored the contemporary global trend. We investigate the effects of China’s market-oriented reforms on wealth inequality using a dynamic general equilibrium model with an incomplete market and idiosyncratic risks. Focusing on the relaxation of private entry and the easing of financial constraints as two pivotal reforms, we show that our model-generated results closely match the actual wealth distribution from 1995 to 2018, with the reform of private enterprise entry accounting for most of the widening wealth disparity. We elucidate the underlying mechanisms of these two reforms using counterfactual simulations and discover that through the savings rate mechanism, the two reforms will collectively form an inverted U-shaped Kuznets curve in wealth inequality as reforms deepen in the future. By calculating the transition dynamics from 1995 to 2035, we confirm that the Kuznets turning point in China lies between 2020 and 2025.

Does relaxing household credit constraints hurt small business lending? Evidence from a policy change in Texas

This paper studies the relationship between household credit and small business loans using the 1997 liberalization of home equity lending in Texas. First, we build a closed economy general equilibrium model that examines two opposing channels: a negative crowding out effect and a positive collateral effect. Our analysis shows that, following a household credit expansion, the crowding out effect dominates and leads to an overall decline in firm borrowing. We test this result empirically by exploiting the liberalization of home equity loans in Texas. The exogenous increase in household credit brought on by the liberalization results in a crowding out of business lending, as small business loan growth declines by roughly 20 percentage points. This negative effect is dampened in counties that experienced stronger house price growth, providing evidence of a subsidiary collateral effect. We further explore the bank-level factors that could influence the strength of the crowding out effect and find that the effect is weaker for banks with easier access to funding and a specialization in business lending.

Carbon taxes, CO2 emissions, and the economy: The effects of fuel taxation in the UK

Carbon taxes remain economists’ preferred policy tool to curb emissions, but they are often criticized by the wider public as ineffective and damaging to the economy. This paper provides new evidence of the effectiveness of carbon taxation through empirical ex-post analysis, using the synthetic control method. We base our quantitative work on a theoretical general equilibrium model with dirty and clean transportation. We take the predictions of the model to data on the UK Fuel Tax Escalator, and estimate the impact of the tax on CO2 emissions, GDP, and transport behaviour. With a potential control pool of OECD countries, we estimate the difference between the observed outcome in the UK and a synthetic counterfactual UK. We find that the tax has a large and significant impact on CO2 emissions from traffic, while there is no discernible impact on GDP or growth. We do not find large changes in driving behaviours, but the available evidence points to a possible switch to rail travel from road travel. Our results are relevant for energy policy makers as they show how a suitable pricing system can effectively reduce climate-damaging emissions without causing macroeconomic damage.

Intelligent transformation, fintech, and green Growth：A general equilibrium analysis based on credit allocation perspective

This paper conducted an in-depth study to elucidate the impact of corporate intelligence transformation and regional financial technology on green economic growth, particularly the role of credit resource allocation. We developed a multi-sector general equilibrium model, integrating the heterogeneity of intelligent transformation in production sectors and accounting for the influence of Fintech on financial institutions. Within this model framework, panel data from 2011 to 2021 at the provincial, municipal, and micro-enterprise levels in China were used to validate the theoretical model through a mixed regression approach. The findings indicate that as intelligent transformation firms receive more credit resources, their potential for green economic growth increases, contributing to reduced regional carbon emissions. Additionally, the excess productivity of intelligent transformation firms has a significant positive impact on regional carbon reduction efforts. Moreover, the advancement of Fintech reduces financial institutional costs, further optimizing credit allocation and lowering overall market interest rates, thereby promoting green development within the region. However, advancements in Fintech may also redirect more credit resources toward low-risk general enterprises, resulting in a credit crowding-out effect for intelligent transformation firms. These findings indicate that, while promoting intelligent transformation, policy measures should also balance the resource allocation effects of Fintech across different types of enterprises.

Shocking projections: The rise of the [x-shock] construction complex in macroeconomics

How do economists think and talk about contingency? They express shock, but not in the typical sense of being surprised. In fact, mainstream economists build models in which shocking events are expected variables. An investigation of nominal forms in the [x-shock] construction (e.g., “technology shock,” “supply shock,” or “monetary shock”) among economists reveals a steep increase in the late twentieth century. We report on a large-scale empirical investigation of influential economic textbooks, top economic journals, and US Federal Reserve documents. Each corpus shows a steep rise in the frequency of nominal [x-shock] beginning in the 1980s. This quantitative analysis lays the groundwork for a qualitative analysis of the various uses of [x-shock] among economists from different schools. First, the rise of nominal shock typifies a process of de-subjectification in which shock moves from its more direct experiential uses toward a role of abstract causation. Second, the steep rise in usage coincides with the rise of general equilibrium models in some economic schools of thought. These models assume a particular type of force dynamic logic. In response, other schools invoke a contrasting force dynamic logic. These developments in the [x-shock] construction show not only semantic change but also the disciplinary logics consolidating that change.

Powering prosperity: Unveiling the impacts of renewable energy policies on economy, employment, and income distribution in Indonesia

This study analyzes the economic and distributional impacts of a Production Tax Credit (PTC) on Indonesia's renewable electricity sector using a Computable General Equilibrium (CGE) model. The simulation spans 2018 to 2030, utilizing the 2018 Social Accounting Matrix (SAM). Results indicate significant reductions in electricity prices by 2025 under two scenarios of total factor productivity (TFP) growth (20 % and 30 %), with continued price decreases through 2030. The study reveals that while urban households and highly educated labour benefit from reduced energy costs and income gains, rural and lower-skilled workers experience fewer advantages, highlighting potential inequalities. The findings underscore the importance of inclusive renewable energy policies to ensure equitable economic outcomes during the energy transition. This research contributes to existing literature by offering new insights into the role of PTC in promoting sustainable energy development in emerging economies like Indonesia, with critical implications for policy design.

Preservation of igneous and metamorphic charnockites in the Paleoproterozoic Prøven Igneous Complex, Rinkian Orogen, central West Greenland

The Paleoproterozoic Prøven Igneous Complex (PIC) of the Rinkian Orogen in central West Greenland comprises a suite of arc-related charnockite plutons, extending over an area of at least 7200 km2. The PIC was emplaced into paragneisses of the Karrat Group during a series of magmatic events between c. 1900 and 1850 Ma. Magmatism was accompanied by high-grade metamorphism and deformation, culminating in granulite facies peak conditions and partial melting at c. 1820 Ma. To unravel the conditions of charnockite formation and granulite facies metamorphism, a detailed petrographic study was carried out on samples from the PIC and the surrounding paragneisses. The rock types studied include i) charnockites from the massive PIC, ii) charnockites and migmatites from the layered lower PIC, iii) migmatites from the surrounding paragneisses, and iv) igneous enclaves from the lower PIC. Charnockites from the massive PIC generally show a magmatic, porphyritic texture and only minor macro-textural evidence of deformation. The lower PIC and paragneisses are both migmatized and exhibit extensive recrystallization with a solid-state crystal-plastic fabric. Igneous enclaves are found within the lower PIC and show an equigranular, igneous texture. Based on the dominant igneous texture it is interpreted that the massive PIC crystallized from a dry magma and was not significantly overprinted during peak metamorphism. Phase equilibrium modelling, Hb-Pl thermometry and Al-in-hornblende barometry constrain the PIC to have been emplaced at 680–795 °C and 4.2–5.4 kbar. By contrast, the lower PIC and paragneiss samples record granulite facies peak conditions of 785–805 °C and 3.4–4.0 kbar, suggesting that both charnockite magmatism and metamorphism took place at relatively shallow crustal levels. Our results are consistent with the P-T conditions recorded by the 1890–1880 Ma Qikiqtarjuaq Plutonic Suite, an arc-type charnockite intrusion on Baffin Island, Canada. A correlation between the tectonothermal events on Baffin Island and in the Rinkian Orogen is proposed, therefore relating the intrusion of the PIC to the collision of the Meta Incognita microcontinent and the Rae Craton.

Reversing climate policy stereotypes: Evidence from an energy-dependent region and China's major economic circles

Achieving decarbonization and industrial transformation in typical energy-dependent regions is a crucial step in mitigating regional climate change. This study constructed a factorial carbon policy equilibrium effect model (FCEE) that integrated input–output analysis, a computable general equilibrium model, factorial analysis, multi-regional input–output, and ecological network analysis. This work explored the internal impact of a composite carbon tax policy that considered the endogenous driving forces of the socioeconomic system on Shanxi Province, a typical energy-dependent region in China, as well as the cascading external effects on China's major economic circles. A significant interaction was found between carbon tax policy, production efficiency progress, and emission efficiency progress, confirming advantage of the composite policy in terms of the environmental–economic benefits. In contrast to common stereotypes, the composite climate policy will promote the clean transformation of the energy structure and gross domestic product growth, and water scarcity in Shanxi Province will be alleviated under the energy–water nexus mechanism. Relying on complex cross-regional networks, China's economic inequality will be indirectly eased. The economic driving forces of the Yangtze River, Chengdu-Chongqing economic circles, and Shanxi Province will be strengthened, promoting system stability and sustainability. It is recommended that Shanxi Province implement a moderate carbon tax policy while improving production efficiency; the intensity of emissions technology reform can be flexibly adjusted according to actual needs. This study provides evidence to support the implementation of climate policy, which is of great significance for other similar regions looking to solve the dilemma of sustainable development.