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A series of novel polylactides bearing an imidazolium group with different anions at one chain extremity were synthesized via ROP of lactide by organocatalysts. The effect of anions was systematically investigated for the first time.

In this paper, we systematically investigated the iROP of l-LA based Ca[N(SiMe3)2]2(THF)2/CTAs binary catalytic systems for the first time. The steric effect, electronic effect and pKa of CTAs all had great influences on the iROP of LA.

A dual Z-scheme NiO/NiFe2O4/Fe2O3 photocatalyst is prepared via incomplete solid state chemical combustion reaction of Ni(OH)2 and Fe(OH)3. The formed perfect interfaces between NiO and NiFe2O4 and between NiFe2O4 and Fe2O3 facilitate the transfers of photo-induced electrons. The photocatalytic degradation of methylene blue and simultaneous production of hydrogen was performed to evaluate the activity of the prepared samples. The dual Z-scheme NiO/NiFe2O4/Fe2O3 (600–2) photocatalyst obtained by heat treatment of Ni(OH)2 and Fe(OH)3 at 600 °C for 2.0 h shows an excellent photocatalytic performance. Additionally, the influences of simulated sunlight irradiation time and methylene blue concentration on the photocatalytic reactions are investigated. Besides, the reusability of sample is assessed via four cycle experiments. Further, a possible mechanism on the photocatalytic reaction is proposed. Maybe, this work would provide an ingenious idea for the construction of dual Z-scheme photocatalyst and the exploration for photocatalytic degradation of organic pollutants with simultaneous hydrogen production.

Diazinon (DZN), a broad-spectrum and highly effective organophosphorus pesticide, is widely being used in agricultural production and household environments. However, massive DZN effluent can be generated during the DZN production process, which will cause devastating effects on the ecosystem and damage human health due to the improper dispose of pesticide effluent before discharging. In this work, hydrodynamic cavitation (HC), a new advanced oxidation technology, was used to degrade DZN in wastewater for the first time. The influences of DZN initial concentration (5.0–15 mg/L), solution pH (4.0–10), temperature (30–50 °C) and some orifice plate geometric parameters (orifice numbers and orifice half angles) on the degradation effect of DZN were investigated. It can be observed that the DZN in solution can be effectively degraded in orifice plate HC system based on three orifices with 45° convergent half angle and the degradation ratio can reach 50.52 % under the operation conditions of 150 min treatment time, 30 °C temperature and pH = 4.0 acidity. Subsequently, the studies of intensifying DZN degradation were also carried out through adding different inorganic oxidants such as potassium peroxodisulfate (K2S2O8), potassium periodate (KIO4) and sodium perchlorate (NaClO4). The maximum DZN HC degradation extent (81.92 %) can be achieved in the presence of K2S2O8 under the optimized conditions. The generated intermediate products in DZN HC degradation process are some low-toxic and low-active substances. And that, these intermediate products can be further mineralized to H2O, CO2 and inorganic ions. On the basis of cavitational yield, the energy consumption analysis has been performed. Overall, this work demonstrates that the HC combined with oxidant K2S2O8 may be a promising strategy for the large-scale treatment of organophosphorus pesticide wastewater.

Currently, the integration of distributed energy generators through virtual power plants in the Internet of Energy is a mainstream method. The complex structure of virtual power plants and the characteristics of distributed energy make it difficult to solve the economic dispatch problems of virtual power plants. In addition, the load of a virtual power plant is unstable and uncertain and thus requires a robust economic dispatch strategy. Because the selection of the set of uncertain conditions is conservative, the traditional robust economic dispatch strategies cannot effectively reduce the cost of virtual power plants. In addition, the traditional methods for solving robust strategies cannot directly solve nonlinear and nonconvex problems. In this article, we propose a scenario-based robust economic dispatch strategy for virtual power plants, aiming to reduce the operational costs of virtual power plants. First, to reduce the conservatism of the strategy, scenario-based data augmentation is adopted for data generation. Through a generative adversarial network, a large amount of scene data are generated to extend the set of uncertain conditions. The scene data cannot only reduce the conservatism but also can be used in the determination of robust strategies. Second, deep reinforcement learning is adopted for historical data training, directly solving nonlinear and nonconvex problems to obtain a robust economic dispatch strategy. As experiments show, with the accurate generation of scene data, the proposed economic dispatch strategy is robust and effectively reduces the cost of virtual power plants.

Nowadays, microgrids (MG) have attracted much attention, as a key technology of the Internet of Energy (IoE). A great deal of research have shown that the hierarchical microgrid is a more novel structure of IoE. Although the hierarchical microgrid model solves the problem of weak power scheduling capability across microgrids, it suffers from severe communications uncertainty, which can lead to communication delay and fluctuation. To obtain the accurate result of the renewable energy accommodation assessment capacity, a hierarchical microgrid model considering communication uncertainty is proposed in this article. The solution to solve the problem of the assessment renewable energy accommodation capacity for hierarchical MG is a hybrid control based on distribution deep reinforcement learning. The temporal difference (TD) generation adversarial network (TD-GAN) is proposed as a value-based method. Compared with the policy-based method, it can better solve the distributed problem in hybrid control with a generation adversarial network (GAN). Moreover, the challenge that the method cannot handle a continuous action space is solved by using a normalized advantage function (NAF). The method similar with the TD error method is employed to train the GAN network. Simulation results using real power grid data demonstrate the effectiveness and accuracy of the proposed method.

Ionic liquids (ILs), 1-alkyl-3-methylimidazolium alanine [Cnmim][Ala] (n = 2, 4), were synthesized and characterized by 1H NMR and DSC. Then, the average temperature vaporization enthalpy, $$ \Delta _\text{l}^{\text g} H_{\text m}^{\uptheta } $$ (Tav), of [Cnmim][Ala] (n = 2, 4) was determined by thermogravimetric method. The difference in heat capacities of ionic liquids between the vapor phase and the liquid phase, $$ \Delta _{\text l}^{g} C_{\text {p,m}}^{\uptheta } $$ , was calculated and $$ \Delta _\text{l}^{\text g} H_{\text m}^{\uptheta } $$ (Tav) was converted to $$ \Delta _\text{l}^{\text g} H_{\text m}^{\uptheta } $$ (298). In addition, the polarity, δμ, of two ILs was estimated based on the $$ \Delta _\text{l}^{\text g} H_{\text m}^{\uptheta } $$ (298). At the same time, the molar surface Gibbs free energy, gs, was calculated, and the traditional Eotvos equation was improved, and its parameters have clear physical significance. In addition, expression for predicting surface tension, γ, of the ILs is obtained by the combination gs with Lorentz–Lorenz equation, and the results show that both are in good agreement with the experimental values.

A new strategy to synthesize hierarchical porous Prussian blue analogues uses nanodomains as the template in a partially miscible ionic liquid/ethanol system, especially near the phase boundary, is developed and the pore size is tuned by controlling the composition of solution in the single phase region. The as-synthesized hierarchical porous catalysts exhibit excellent catalytic performance in the epoxidation of styrene.

The binary mixtures composed of 1-ethyl-3-(2-methoxyethyl)-imidazolium bis(trifluoromethylsulfonyl)imide [C22O1IM][NTF2] and alcohols were prepared, and the density and viscosity were measured firs...

Series of hydrophobic hexafluoroantimonate [Cneim][SbF6] (n = 4, 5, 6) were synthesized and characterized by 1H NMR and ESI-MS. It is obvious that the reactive hydrogen is replaced with ethyl group on N-3 position of imidazole cation, and it could have an effect on the corresponding physicochemical properties. The density, surface tension, refractive index, and conductivity of the hydrophobic ILs [Cneim][SbF6] (n = 4, 5, 6) were measured in the temperature range of (293.15 to 343.15) ± 0.05 K with an interval of 5 K. The volume properties and surface properties were calculated. According to Kabo’s method, the vaporization enthalpy was also calculated, and the polarities were predicted. The applications of the mole surface Gibbs free energy were investigated. In addition, the relationship between the conductivity and temperature was also explored, and the molar conductivity and diffusion coefficient for ILs were obtained.

We study contests in which contestants are homogeneous and have convex effort costs. Increasing contest competitiveness, by making prizes more unequal, scaling up the competition, or adding new contestants, always discourages effort. These results have significant implications: although often criticized as evidence of laxity or cronyism, muting competition (e.g., adopting softer grading curves or less high-powered promotion systems) can both reduce inequality and increase output. Holding promotion contests at the division level rather than the firm level can boost employees’ effort. Our results are also consistent with personnel policies that feature egalitarian pay systems and dismissal of worst-performing employees.

The photocatalytic conversion of toxic heavy metal ions with the simultaneous degradation of pollutants is considered to be a promising wastewater treatment strategy. In this study, a novel Z-scheme (CNT-Ni2P-CNT/Er3+:Y3Al5O12)@Bi12GeO20 photocatalyst is successfully prepared. This photocatalyst displays excellent photocatalytic activity in the conversion of Cr(VI) with the simultaneous degradation of Rhodamine B under solar light irradiation, which is ascribed to the enhanced separation efficiency of photogenerated carrier, increased oxidation surface and broadened light response range. Certain influencing factors, such as the irradiation time, initial concentrations and catalyst dosage, are discussed. These results show that when the concentrations of Cr(VI) and Rhodamine B are 15 mg/L and 5.0 mg/L, respectively, and the photocatalyst dosage is 1.0 g/L, the highest conversion ratio (93.66%) and degradation ratio (73.34%) can be obtained. This work utilizes solar light to achieve the conversion of toxic heavy metal ions with the simultaneous degradation of pollutants.

The aim is to investigate whether elevated risk taking in asset market experiments driven by rank-based performance incentives decrease if removing a time limit on choices and minimizing complexity...

PurposeThe purpose of this paper is to investigate how social comparison and motivation to compete account for elevated risk-taking in fund management corroborated by asset market experiments when performance depends on rank-based incentives.Design/methodology/approachIn two laboratory experiments, university students (n1 = 240/n2 = 120) make choices between risky and certain outcomes of hypothetical sums of money. Both experiments investigate in which direction risky choices in an individual condition (individual risk preference) are shifted when participants compare their performance to another participant's performance (social comparison), being instructed or not to outperform the other (incentive to compete).FindingsIn the absence of incentives to compete, participants tend to minimize the differences between expected outcomes to themselves and to the other, but when provided with incentives to compete, they tend to maximize these differences. An independent additional increase in risk-taking is observed when participants are provided with incentives to compete.Originality/valueOriginal findings include that social comparison does not evoke motivation to compete unless incentives are offered and that increases in risk-taking depend both on what the other chooses and the incentives.

Nowadays, with a large of complicated geography of Distributed Energy Sources (DES), how to integrate distributed renewable energy source and reduce the operational costs by Virtual Power Plant (VPP) becomes a mainstream problem in Internet of energy. The traditional method of energy integration and operational cost optimization utilizes the cloud computing technology to centralized control the computational task, which increases the burden of computing. According with the development of information communication technology, such as Internet of Things and 5G, edge computing technology is an effective way to offload computational task to the edge side of 5G networks. Moreover, with the increase of collected data, it becomes a key point to effectively improve the computing power of edge nodes in edge computing. Currently, machine learning is an effective way to process the big data. Based this situation, it leads the combination of machine learning and edge computing. In this paper, the Edge Intelligence (EI) structure is proposed to solve the Economic Dispatch Problem (EDP) in VPP of Internet of Energy. Compared with the traditional edge computing, the proposed EI structure inherits its original features which reduce the burden of cloud computing, and also the proposed EI structure improves the computational power of edge computing. Through the splitting model and deploying the particle model in the terminal, it is facility to real-time control and take the less costs of VPP. Due to the transmission between the splitting models with counterpart, it transmits the part information and gradient information, which effectively reduces the consumption of communication. The proposed method has verified the effectiveness and feasibility through the numerical experiments of real application data sets.

A novel 3D electrochemically reduced graphene oxide (ERGO) porous gelatum material was self-assembled on graphite plate (GP) by the simple and controllable electrodeposition method to construct a new-type integrated electrode (ERGO-GP) for all vanadium redox flow batteries (VRFBs). Benefited from the ideal preparation method, a porous and gradient microstructure of ERGO was formed easily and facilitated the electrolyte, ions and electron transport simultaneously. Besides, the direct growth of ERGO on GP could reduce the contact resistance between the reaction layer and the conduction layer effectively. As a result, the electrochemistry and battery performance for the ERGO-GP as both negative and positive electrode of VRFBs were better than the common carbon felts (CF) and GP electrode system (CF-GP) due to the lower polarization. The obtained results also indicated the great promise of this material for application in other flow redox batteries and helped us to improve the design of carbon-based porous electrodes.

In this work, a novel Eu

Uncompetitive contests for grades, promotions, retention, and job assignments, which feature lax standards and limited candidate pools, are often criticized for being unmeritocratic. We show that, when contestants are strategic, lax standards and exclusivity can make selection more meritocratic. When many contestants compete for a few promotions, strategic contestants adopt high-risk strategies. Risk-taking reduces the correlation between performance and ability. Through reducing the effects of risk-taking, “Peter-Principle” promotion policies, which entail promoting some contestants that are unlikely to be worthy, can increase the overall correlation between selection and ability, and thus further the goal of meritocratic selection.

One puzzling feature of domestic private equity (PE) funds in emerging markets is that such funds often have a “short fuse”, i.e., a much shorter lifespan than their developed market counterparts. Based on a simple agency model, we propose an explanation for this puzzle. We show that, under a long fuse, PE managers have incentives to game performance-based compensation schemes by opportunistically timing investments and burning money when early investments fail. Shortening the fuse restricts timing opportunism, but alleviates money-burning incentives only if managerial compensation is sufficiently concavified or the contract stipulates substantial investors' hurdle returns. Both of these options can force managers to concede rents to investors. Thus, managers face a tradeoff between rents and agency costs. In emerging markets, where agency costs are high, managers use a short fuse with incentive compatible compensation schemes to minimize agency costs. In contrast, in developed markets, where agency costs are low, managers use a long fuse to preserve rents. Based on these results, we further draw predictions on fund performance, managerial behavior, and investor rents for both long-fused developed-market funds and short-fused emerging-market funds. We also predict that, when institutional infrastructure in emerging markets improves and when domestic PE managers in emerging markets gain more experience, domestic PE funds in emerging markets will adopt the long-lifespan PE contracts typical in developed markets.