Scarcity Price Research Articles

Scarcity effect in collaborative fashion consumption via the C2C online platform: moderating effect of consumer price sensitivity and gender

ABSTRACT This study investigates the effect of scarcity on purchase intention in a collaborative fashion consumption situation using a C2C platform. Furthermore, it examines the moderating effect of consumer price sensitivity and gender. A mixed experimental design method of 2 (scarcity level: high vs. low) × 2 (consumer price sensitivity: high vs. low) × 2 (gender: male vs. female) was applied. This study found that although the scarcity level did not directly affect purchase intention, the effect was moderated by price sensitivity. Consumers with high price sensitivity show greater purchase intention under low scarcity, whereas consumers with low price sensitivity show greater purchase intention under high scarcity. Moreover, the interaction effect of scarcity level and price sensitivity on purchase intention significantly differed for women, but not for men. This study provides insights for C2C platform marketers to devise marketing strategies considering the scarcity of second-hand fashion products and consumer traits.

Electricity Retail Rate Design in a Decarbonizing Economy: An Analysis of Time-of-use and Critical Peak Pricing

Currently, the main component of most U.S. consumers’ electricity bills is based on a constant price per kWh consumed. As intermittent renewable resources and flexible loads that can be shifted within days (such as electric vehicle charging) gain prominence in the electricity system, the efficiency gains to be realized from basing bills instead on wholesale spot prices increase. There is little political support for this change, however. We focus on second-best alternatives: time-of-use (TOU) rates and critical peak pricing (CPP). We introduce alternative assessment criteria that focus on intra-day load shifting. Using historical data, we find that TOU rates can reasonably replicate the intra-day load-shifting incentives provided under spot pricing. Thus, TOU rates, especially when complemented with CPP involving load control during infrequent scarcity price events, can be considerably more socially valuable than previously estimated.

Price discrimination in mobile gacha games: A comprehensive study of the scarcity–pricing, gachaing–user profiling, and recharging–profiting models

AbstractPrice discrimination (PD) in mobile gacha games differs from that in e‐commerce platforms due to its reliance on the concealed “probability” mechanism, which appears transparent but is actually controlled, making it harder to detect and regulate by society. To confirm the existence of PD in mobile gacha games, a comprehensive analysis of its operational modes was conducted through extensive participatory observation and in‐depth interviews with over 30 domestic gamers, game developers, and data analysis website founders. The study revealed that, contrary to academic definitions, PD does indeed occur in mobile gacha games, characterized by three interconnected models: the scarcity–pricing model, gachaing–user profiling model, and recharging–profiting model. By examining the interrelated models that comprise the PD process, concentrating on China as a special context, and offering insightful information on the effects of PD on consumer behavior and economic platforms, this study makes a noteworthy and novel contribution to the understanding of PD within the realm of mobile gacha games. The research examines the influence of PD on consumer behavior and economic decision‐making processes. Furthermore, the research discusses the difficulties of controlling PD in mobile gacha games, particularly due to the opacity of the “probability” mechanism. In conclusion, recommendations aimed at addressing the issue of PD within the realm of mobile gacha gaming in China are presented, drawing upon Lawrence Lessig's framework on “Four modalities of restraining behavior in cyberspace.”

Impulse buying behavior during livestreaming: Moderating effects of scarcity persuasion and price perception

This research aimed to identify the factors that influence impulse buying behavior during livestreaming and advance the existing literature based on a proposed conceptual framework grounded in the stimulus-organism-response (S–O-R) model. We also tested the moderating effects of price perception and scarcity persuasion. An online self-administered questionnaire was used to collect data from 837 Chinese participants aged over 18 years. The data were analyzed using partial least squares structural equation modeling using Smart-PLS version 4.0. The findings showed that susceptibility to social influence, impulse buying tendency, cognitive reactions, affective reactions, and the urge to buy impulsively are statistically significant predictors of impulse buying during livestreaming, with price perception and scarcity persuasion as moderators. The study expands the S–O-R model for livestreaming impulse buying in e-commerce context, highlighting its multifaceted nature and revealing the mediating role of Urge to Buy Impulsively in translating cognitive and emotional factors into impulse buying behavior. These insights offer practical guidance for marketers to design tailored strategies that leverage psychological triggers and external cues to enhance consumer engagement and encourage desired behaviors, ultimately leading to more effective marketing campaigns and improved consumer experiences.

STIMULUS RESPONSE THEORY: THE CONSTRUCTION OF IMPULSE BUYING ON SHOPEE LIVE SELLING

Scarcity messages have never been researched globally, while price discounts and free shipping taglines have different results from previous research or journals. This research aims to determine the effect of scarcity messages, price discounts, and free shipping taglines on impulse buying on Shopee live selling. The research method used in this research is quantitative with multiple linear regression as the data analysis method. The population of this research is all management study program students from the class of 2020 with the sample determination method being purposive sampling. The number of samples used was 155 students which was determined using the Slovin formula. The results of this research show that scarcity messages have a significant positive influence on impulse buying on Shopee live selling. Price discounts have an insignificant positive effect on impulse buying on Shopee live selling. And the free shipping tagline has an insignificant negative effect on impulse buying on Shopee live selling. Simultaneously, scarcity messages, price discounts and free shipping taglines have a significant influence on impulse buying on Shopee live selling.

A Capacity Adequacy Mechanism Based on Optional Option and Its Impact on Generation Mix Equilibrium

Due to the missing money problem, it is a challenging task to maintain generation capacity adequacy with increasing shares of zero-marginal-cost renewable energy resources. Multiple capacity adequacy mechanisms (CAMs), such as scarcity pricing, capacity payment, capacity market, and reliability option, have been proposed and implemented, each having its own pros and cons. Here, we propose a hybrid CAM called optional option. The hybrid CAM allows scarcity pricing and reliability option to co-exist. Market participants, with diverse degrees of risk aversion and diverse forecasts of future duration of scarcity, can self-select the CAM best suited to themselves. We also present a method to efficiently derive the generation mix equilibrium under the CAM, by using the theory that the profits of all generator types approach zero in the long-term equilibrium. Simulation results show that the proposed CAM enables Pareto improvement by letting market participants be better off than being restricted to only one CAM. The results also show the effectiveness of the algorithm to calculate the generation mix equilibrium.

A mixed-ligand Co metal-organic framework and its carbon composites as excellent electrocatalysts for the oxygen evolution reaction in green-energy devices.

Oxygen evolution reaction (OER) electrocatalysts are frequently made from noble metal-based oxides like ruthenium/iridium oxides. However, because of their scarcity and high price, researchers are now focusing on creating innovative OER catalysts based on affordable transition metals that have improved electrical conductivity and accessibility to active sites. Metal-organic frameworks (MOFs), a unique class of inorganic materials with excellent physical and chemical properties, have witnessed significant progress in promising green energy systems. In this work, a novel mixed-ligand metal-organic framework [Co(μ-1κN,2κN'-BDP)(μ3-1κoo',2κo''2κo'''-BTC)]n·nH2O (BDP = boron-dipyrromethene or BODIPY; BTC = benzene tricarboxylate) denoted as CoBDPMOF has been synthesized, and its composites with different carbon materials have been designed. Compared to the pristine MOF, the composites showed enhanced electrocatalytic activity toward the oxygen evolution reaction (OER) in alkaline media. In addition, the CoBDPMOF with activated carbon showed the highest OER performance with a low Tafel slope (82 mV dec-1) and the highest j600 (59.8 mA cm-2), outperforming noble metal IrO2, the OER benchmark electrocatalyst. This study presents new insights into the design and application of CoBDPMOF-based materials for energy conversion and suggests promising avenues for further research and development in electrocatalysis.

Is Climate Finance Helping Stabilise Food Prices in Sub-Saharan Africa?

This study explores the potential impact of climate finance (cf) on foodprices in Sub-Saharan Africa (SSA) as climate change continues to createfood scarcity and increase food prices. The study analyses data from43 SSA countries between 2006 and 2018 using a panel fixed effect modelwith Driscoll-Kraay standard errors and methods of moments quantile regressions(MMQR). The findings indicate that countries in SSA that receivemore cf, improve their fight against corruption, have good rainfall patterns,experience reduced extreme temperatures, have depreciated currencies,larger populations and higher GDP growth, reduce food imports, increasedomestic food supply, and demonstrate high governance and socialreadiness are likely to experience stable or reduced food prices. Based onthese results, the study recommends that SSA governments prioritise anticorruptionefforts to earn donor trust and increase CF, ultimately leadingto lower food prices in the sub-region. Further, the findings indicatethat good rainfall patterns reduce food prices: this shows the need for SSAcountries to invest in policies that lead to reliablewater supply as irrigation.

Strong Metal-Support Interaction – a Tool for Enhancing the Hydrogen Evolution Reaction Performance

Renewable and green energy transition and meeting ever-increasing energy demands are among modern society's most pressing challenges. Currently, the world's energy systems rely on fossil fuels, leading to significant environmental pollution, including anthropogenic CO2 emissions and subsequent climate changes. The concept of hydrogen economy was first proposed half a century ago as a way to overcome these challenges by using hydrogen as the primary energy carrier instead of fossils.1 However, hydrogen production remains one of the significant obstacles to realizing the hydrogen economy, as steam reforming of methane derived from natural gas is still the dominant method of industrial-scale production, contributing significantly to the undesired emissions. Water electrolysis powered by renewables such as wind and sun energy is a sustainable way to produce high-purity hydrogen. In electrolyzers, hydrogen is obtained at the cathode side through the electrochemical hydrogen evolution reaction (HER), while the oxygen evolution reaction (OER) occurs at the anode. The HER is one of the most intensely studied electrochemical processes as it is of paramount importance for both fundamental and applicable aspects of electrocatalysis and physical chemistry in general. Traditionally, Pt has been known as the best monometallic HER catalyst due to its close-to-optimal interaction with adsorbed hydrogen atoms, which are reaction intermediates.2 However, due to its scarcity and high price, significant research efforts are being invested in designing alternative Pt-free electrocatalysts for (not only) HER. While promising results have been reported with different abundant materials such as sulfides, nitrides, carbides, and phosphides, their applicability is still challenged by rather inferior activity with respect to Pt and rapid deactivation, especially in corrosive acidic media. Currently, state-of-the-art HER catalysts are based on Pt nanoparticles dispersed over high-surface-area carbon supports (Pt/C). The main downside of such composites is the weak interaction between carbon and Pt particles, which means that support cannot affect the intrinsic activity of Pt sites. Moreover, this weak interaction results in the degradation of Pt/C due to particle detachment, agglomeration, or coalescence during HER. Upgrading the overall performance of Pt/C may be achieved by employing alternative supports able to trigger strong metal-support interaction (SMSI). SMSI can alter the electronic structure of the metallic active sites and increase their activity, while also it can lead to the stronger anchoring of nanoparticles with the support, improving stability. Different materials, such as pre-functionalized carbons, carbides, and metal oxides, have been reported to be able to provide SMSI.In this work, we investigated HER on a carbon-ceramic catalyst composed of Pt nanoparticles supported on titanium oxynitride (TiONx) embedded on reduced graphene oxide nanoribbons (Pt/TiONx).3 TiONx was obtained by incorporating nitrogen into TiO2 and provides the main merits of carbon supports, such as electrical conductivity and high surface area, combined with the ability to trigger SMSI. The screening of the electrocatalytic performance of the Pt/TiONx composite for HER revealed enhancement with respect to the Pt/C benchmark, which we ascribe to the effect of the TiONx substrate via SMSI. To confirm this, XPS was performed to compare the electronic states of Pt in Pt/TiONx and Pt/C catalysts, which revealed the ability of TiONx to trigger SMSI. DFT calculation provided additional confirmation of SMSI between the TiONx support and Pt nanoparticles and its impact on both HER activity and stability enhancement. The results presented in this work open up a perspective of using TiONx as an alternative support able to improve the catalytic performance of various active sites for different electrochemical reactions. References (1) Bockris, J. O. M. The Hydrogen Economy: Its History. Int J Hydrogen Energy 2013, 38 (6), 2579–2588. https://doi.org/10.1016/j.ijhydene.2012.12.026.(2) Hansen, J. N.; Prats, H.; Toudahl, K. K.; Mørch Secher, N.; Chan, K.; Kibsgaard, J.; Chorkendorff, I. Is There Anything Better than Pt for HER? ACS Energy Lett 2021, 1175–1180. https://doi.org/10.1021/acsenergylett.1c00246.(3) Smiljanić, M.; Panić, S.; Bele, M.; Ruiz-Zepeda, F.; Pavko, L.; Gašparič, L.; Kokalj, A.; Gaberšček, M.; Hodnik, N. Improving the HER Activity and Stability of Pt Nanoparticles by Titanium Oxynitride Support. ACS Catal 2022, 12 (20), 13021–13033. https://doi.org/10.1021/acscatal.2c03214. Figure 1

Investigation of the degradation of proton exchange membrane water electrolysis cells using electrochemical impedance spectroscopy with distribution of relaxation times analysis

Reduction of catalyst loading on Proton Exchange Membrane (PEM) Electrolysis Cells (EC) is needed because of scarcity and high price of the catalyst. Monitoring the degradation of these cells is important to be able to allocate the different processes taking place. Electrochemical Impedance Spectroscopy (EIS) might be suitable for this purpose, but in its usual implementation, the system and the contribution of its components to the total resistance must be already known to build a suitable equivalent circuit model (ECM). Furthermore, the overlap of different processes in the Nyquist and Bode plots hinders the identification of single components of the system. The Distribution of Relaxation Times (DRT) analysis converts the EIS data into a distribution of time constants of individual processes. The contribution of each component to the full cell resistance can be identified by varying different operation parameters. In this work, a PEMEC with low iridium loading was analyzed by DRT and the faradaic processes were identified. A long-term test was carried out and the degradation of the cell was investigated by DRT analysis, to determine the components and processes which limit the cell performance.

Review Presentation of Different Economic Order Quantity (EOQ) Models and Their Application

In the context of inventory management, this review presentation offers a thorough overview of several Economic Order Quantity (EOQ) models and their real-world uses. It explores the fundamental EOQ model and broadens to incorporate models that account for perishable items, quantity discounts, and scarcity prices. The talk also looks at the many sectors in which these models are used to optimize order amounts, save costs, and improve operational efficiency. Businesses may improve their inventory control strategies, realize considerable cost savings, and increase performance by making educated decisions based on a thorough grasp of the various EOQ models and their practical implementations.

Layer-by-Layer Nanofluidic Membranes for Promoting Blue Energy Conversion.

Access to and use of energy resources are now crucial components of modern human existence thanks to the exponential growth of technology. Traditional energy sources provide significant challenges, such as pollution, scarcity, and excessive prices. As a result, there is more need than ever before to replace depleting resources with brand-new, reliable, and environmentally friendly ones. With the aid of reverse electrodialysis, the salinity gradient between rivers and seawater as a clean supply with easy and infinite availability is a viable choice for energy generation. The development of nanofluidic-based reverse electrodialysis (NRED) as a novel high-efficiency technology is attributable to the progress of nanoscience. However, understanding the predominant mechanisms of this process at the nanoscale is necessary to develop and disseminate this technology. One viable option to gain insight into these systems while saving expenses is to employ simulation tools. In this study, we looked at how a layer-by-layer (LBL) soft layer influences ion transport and energy production in charged nanochannels. We solved the steady-state Poisson-Nernst-Planck (PNP) and Navier-Stokes (NS) equations for three different types of nanochannels with a trumpet geometry, where the narrow part is covered with a built-up LbL soft layer and the rest is a hard wall with a surface charge density of σ = -10, 0, or +10 mC/m2. The findings show that in type (I) nanochannels, at NPEL/NA = 100 mol/m3 and pH = 7, the maximum power output rises 675-fold as the concentration ratio rises from 10 to 1000. The results of this study can aid in a better understanding of energy harvesting processes using nanofluidic-based reverse electrodialysis in order to identify optimal conditions for the design of an intelligent route with great controllability and minimal pollution.

Core-Shell Structured Water Oxidation Anode for Minimum Platinum Group Metal Usage in Proton Exchange Membrane Water Electrolyzer

The development of enhanced electrocatalysts and optimization of electrode structures are of great importance for the practical and widespread deployment of proton exchange membrane water electrolyzers (PEMWEs). In particular, the scarcity and high price of Ir are considered to be bottlenecks inhibiting the large-scale commercialization of PEMWEs. Even compared with Pt, a rare-earth metal with a low production rate of 150~200 tons per year, Ir availability is extremely limited, as only a few tons per year are produced [1]. Therefore, It is envisioned that the Ir loading on the anode should be lowered (e.g., to 0.05 mg/cm2) to meet the annual demand for the PEMWE system installation on the scale of ≈5 GW by 2040 [2].To reduce the usage of rare-earth metals in PEMWEs, a highly active water-oxidizing anode was fabricated by depositing a core–shell structured catalyst on a titanium porous transport layer (Ti PTL). Earth-abundant metal-based iron-nitride (Fe2N) nanostructure was deposited on a Ti PTL by sequential hydrothermal and nitridation reaction. The prepared Fe2N nanostructure was then passivated by thin, electrodeposited iridium-oxide films (EIROF). Fe2N@EIROF core-shell structured anodes exhibited substantially low ohmic and mass-transfer resistances, leading to a high current density of 4.50 A/cm2 (@1.9 Vcell). The unique Fe2N@EIROF core-shell structure enhanced PEMWE performance in terms of Ir mass activity by substituting inner Ir atoms with earth-abundant metal-based iron nitride. A high Ir mass activity of 103 A/mgIr (@1.9 Vcell) was achieved by reducing Ir loading amount to 0.064 mg/cm2 on the anode. The chemical instability of transition metal-based supports in a PEMWE operating condition was overcome by the passivation with Ir catalyst layers. As a result, the prepared core–shell-structured catalysts were stable under the PEMWE operating condition achieving high Ir mass activities.[1] K. Nose, T.H. Okabe, Chapter 2.10 - Platinum Group Metals Production, in: S. Seetharaman (Ed.) Treatise on Process Metallurgy, Elsevier, Boston, 2014, pp. 1071-1097,[2] C. Minke, M. Suermann, B. Bensmann, R. Hanke-Rauschenbach, Is iridium demand a potential bottleneck in the realization of large-scale PEM water electrolysis?, Int. J. Hydrogen Energy, 46 (2021) 23581-23590

A harmless slagging treatment to separate key impurities from Fe-PGMs alloys for improving the recovery ratio of PGMs from spent auto-catalysts

Spent auto-catalysts are main secondary resources for platinum group metals (PGMs) Pt, Pd, and Rh. Considering their scarcity and excessive prices, recycling PGMs from spent auto-catalysts is important for sustainability of PGMs. The dissolution of Fe-PGMs alloys in acids is an important step that significantly influences the recovery ratio of PGMs from spent auto-catalysts by smelting using Fe as a PGMs collector. However, the presence of impurities, such as Si, in Fe-PGMs alloys makes them difficult to completely dissolve in acids, resulting in low PGMs recovery ratios. Few studies have been reported on solutions for eliminating these impurities from the Fe-PGMs without loss of PGMs. In this study, a green slag refining process was proposed to remove key impurities from Fe-PGMs alloys. Different compositions of CaO-SiO2-Al2O3-FeOx and CaO-Al2O3-FeOx slags were investigated to improve the removal of impurities such as Si, Ca, Mg, Ti, and Al in Fe-PGMs to increase the total recovery ratios of PGMs; the removal rates of Si, Ca, Al, Mg, and Ti were 99.2 %, 99.8 %, 99.8 %, 99.7 %, and 99.9 %, respectively, when a CaO-Al2O3-35Fe2O3 (C/A = 1.5; S/A = 1.2) slag was used at 1843 K. After slagging treatment, Fe-PGMs alloy could be easily dissolved in aqua regia, which is conducive to subsequent ion exchange or supramolecular recognition process to obtain high PGMs recovery ratios. This slagging treatment is considered a green and economic approach as the residual slag exhibits no hazardous elements and can be recycled or reused to prepare other products.

A Market Framework for a 100% Renewable Energy Penetration Spot Market

The global installed capacity of renewable energy sources (RESs) is increasing rapidly. The 100% RESs power supply is being pursued. When renewable energy penetration tends to be 100%, the source-load coordination problem becomes extreme. The problems of market failure caused by the near-zero marginal cost of RESs and the scarcity pricing of flexible resources (FRs) participating in the rapid energy deviation balance need to be solved. Accordingly, a spot market framework including the day-ahead renewable energy temporal capacity market and the real-time energy sharing market is proposed in this paper. The RESs and FRs are decoupled to ensure that the homogenous commodities compete together. In the day-ahead stage, to obtain the locational marginal price with the guiding role of resource allocation, the fixed cost of the RESs is apportioned to obtain the spatial-temporal capacity price. In the real-time stage, a price-driven distributed energy sharing mechanism is proposed. It is proven that the sharing mechanism can achieve optimum social welfare and satisfy incentive compatibility. The simulation verifies that the new framework can solve market failure. The real value of FRs is discovered when a price consensus is reached.

Evaluating long-term profile of demand response under different market designs: A comparison of scarcity pricing and capacity auction

Demand response (DR) is widely acknowledged as a promising solution to maintain the capacity adequacy of the power system. In China, DR is now shifting from government pricing to market-oriented pricing. However, the market pricing mechanism to be adopted is still inconclusive and the long-term influence of different pricing mechanisms on incentivizing DR remains unknown. Moreover, the market contains multiple participants, various strategic behaviors, and non-linear clearing procedures while traditional optimization models cannot capture the complex dynamics. This paper adopts a system dynamic (SD) method to evaluate the long-term profile of DR under different market designs. Firstly, an investment decision model of generation companies is formulated to simulate the growth tendency of capacity supply in a long-term period. Secondly, in the context of unmatured marketization, the growth tendency of DR and retail market users are modeled by Bass diffusion. Finally, scarcity pricing and capacity auction are applied to investigate the incentive influence of different market designs on DR. Through the simulation to 2035, the results show that compared with the energy-only market, scarcity pricing, and capacity auction can raise the capacity of DR from 3.12% to 7.58% and 9.21%, respectively.

Mengoptimalkan Hasil Panen Padi Menggunakan Metode Goal Programming Dengan Pengaplikasian Nutrisi PGPR

Papungan’s one of the villages in Blitar Regency where most of the population are farmers and mostly cultivate rice crops. The effort was made by farmers to meet the needs of the community, but still in limited quantities. From the results of interviews with farmers in Papungan village, they complained a lot because the rice crop was still relatively low, due to the scarcity and high price of fertilizers. By making PGPR (Plant Growth Promoting Rhizobacteri) organic nutrients, it is a consortium of bacteria that actively colonize plant roots which play an important role in increasing plant growth, crop yields and land fertility. This study aims to optimize the profitability of rice farming in Pappungan Village. The results of the profit optimization calculation using the Goal Programming method. This study uses primary and secondary dta, and the purpose of this study aims to solve the problem of limited resources optimally with the Goal Programming method. Based on the results of the discussion of calculations using the goal programming method, the conclusion of the optimization of rice crops and applied using LINGO software, obtained optimal results, namely Z = 424.7647 with three goals achieved, among others, the production yield reached 27,640 Kg and the selling price of rice crop production reached Rp 18,000 / Kg with production costs required for rice crop production for per hectare of Rp 61,980,000. For the results of the goal achieved (goal) optimization of crop patterns, Papungan Village farmers are recommended to plant type B rice.

The interaction of wholesale electricity market structures under futures with decarbonization policy goals: A complexity conundrum

Competitive wholesale electricity markets can help facilitate energy system decarbonization by incentivizing investments in clean energy technologies that meet evolving system needs. We explore market structure impacts on generator operations and deployment by risk-averse, heterogeneous investor firms using the Electricity Markets and Investment Suite – Agent-based Simulation (EMIS-AS) model. We apply clean energy targets of 45%–100% by 2035 considering energy, ancillary services, capacity, and clean energy credit products and pricing and eligibility rules. Results highlight a complexity conundrum, whereby finding the “right” market design to achieve decarbonization goals and avoid unintended consequences can be a highly-nuanced, non-incremental challenge. Carefully designed energy-only markets can achieve the same clean energy targets as capacity market structures but with different revenue and profitability outcomes. Operating reserve demand curve-based scarcity pricing can substitute capacity markets for similar deployment outcomes. Carbon pricing alone is most effective at achieving decarbonization levels at low clean energy targets, and clean energy credit markets and carbon pricing are substitutionary at high clean energy targets. Restricting technology participation in capacity and operating reserve markets can impact deployment and operations, even for nonrestricted technologies. Adding an inertia product with fast frequency response yields insufficient provision at high clean energy targets, but work is needed to understand frequency requirements and capabilities.

Development of polymer inclusion membranes for palladium recovery: Effect of base polymer, carriers, and plasticizers on structure and performance

Recently, palladium is widely used in electronics, catalysis, electroplating, and fuel cells. The recovery of precious metals has become very important due to their scarcity and high price. The adsorption method which is generally used in polymer inclusion membranes is both effective and simple because, for that reason, the retention and mechanism of chemicals were shown to be significantly influenced by precious metal adsorption on the membrane. In this study, polymer inclusion membranes were produced and characterized by using different base polymers, carriers (Aliquat 336, trioctylamine (TOA)), and plasticizers (2-nitrophenyl octyl ether (NPOE)). The palladium adsorption capacities of the membranes were examined in detail in terms of different pHs, temperatures, contact times, and membrane contents. The optimum pH was determined as 2 for all membranes. In addition, the temperatures and contact times of the membranes containing cellulose triacetate (CTA), polyvinyl chloride (PVC), and polyvinylidene fluoride (PVDF) were 35 °C-240 min, 55 °C-90 min, and 35 °C-180 min, respectively. According to the effect of membrane type, the best results were obtained for 40 % CTA-20 % Aliquat-40 % TOA, 40 % PVC-20 % Aliquat-40 % TOA, and 40 % PVDF-40 % Aliquat-20 % NPOE for each base polymer.

Identifying optimal capacity expansion and differentiated capacity payments under risk aversion and market power: A financial Stackelberg game approach

We investigate how capacity payments in combination with scarcity pricing of energy can ensure resource adequacy in electricity markets, defined as the ability of supply and other resources to provide enough energy and capacity to meet demand under steady-state operating conditions. This work generalizes models for determining capacity payments by deriving second-best discriminatory payments by resource type that account not only for the “missing money” market failure that arises from energy price caps, but also for market power in the capacity market and differences in risk tolerance among resource types that can arise from failures in risk and capital markets. A bi-level equilibrium-constrained optimization model is proposed to define second-best capacity payments in a static long-run setting, considering the impacts of those payments on the mix and cost of generation investment and energy outputs. The lower-level suppliers play a Nash game to determine the generation mix under a capacity payment scheme, while the upper-level regulator considers consumer welfare and resource adequacy. We introduce an equivalent formulation via a variational inequality approach, and find conditions for the solution to exist. Discriminatory payments are found to be second-best when there are market power in the investment game, price caps in energy markets and imperfections in risk markets that lead to diverse risk attitudes.