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We find that manufacturing firms adopt more conservative capital structures in response to the Nitrogen Oxides (NOx) Budget Trading Program (NBP) of 2004, a regional cap-and-trade program aimed at mitigating the NOx emissions of power plants in 11 midwestern and southeastern states in the United States. Our further analysis demonstrates that, because the NBP induces an electricity price shock, it affects manufacturers’ financial decisions by raising their operating leverage and distress risk. We also find that firms respond to the NBP’s adoption heterogeneously: they adjust their financial leverage more dramatically when facing greater electricity intensity, financial distress threats, or competitive pressure. In addition, firms adapt not only capital structure, but also other financial policies in response to the regulation. Overall, our study shows that climate policy risk constitutes an essential consideration in firm financial decisions. It also highlights potential unintended consequences of policy responses to climate change for the corporate sector. This paper was accepted by George Serafeim, Special Issue of Management Science: Business and Climate Change. Funding: The authors gratefully acknowledge generous financial support from the Alliance Manchester Business School Strategic Research Investment Fund. Supplemental Material: The data files and online appendix and data are available at https://doi.org/10.1287/mnsc.2022.4617 .

As a geochemical tracer in mantle studies, lithium isotopes play an important role in diffusion and fractionation in major mantle minerals. Olivine and its high-pressure phases, wadsleyite and ringwoodite, are considered to predominate in the upper mantle and transition zone on the earth. We carried out simulations of lithium isotopes’ diffusion and fractionation in Mg end member olivine and its high-pressure phases to learn the details of the signatures of lithium isotopes preserved in mantle materials. In this work, the diffusion and fractionation mechanisms between different lattice sites of lithium isotopes in forsterite (Mg2SiO4), wadsleyite (β-Mg2SiO4) and ringwoodite (γ-Mg2SiO4) at the atomic level are studied using empirical atomistic simulation techniques. It is found that Li can pass through the high-pressure phases (wadsleyite and ringwoodite) energetically much easier due to the low migration energy barriers via either substitutional or interstitial mechanism. The activation energy is high for Li diffusion along the interstitial path in the forsterite and decreases drastically with the assist of Mg vacancies. The temperature-dependent fractionation for two Li isotopes between two different lattice sites is calculated at the temperatures from 300 to 2500 K. This behavior generates the lighter Li storage in the near-surface mantle-derived rocks and provides insights into zoning and composition of lithium isotopes in olivine and its high-pressure phases.

A novel bipolar compound triphenylamine-dibenzothiophene S,S-dioxide (TPAFSO) based on a dibenzothiophene-S,S-dioxide (DBTO) moiety and a triphenylamine (TPA) unit, in which the TPA unit is linked at its 4-position to the DBTO group at its 3,7-position, is designed and synthesized. The experimental results clearly show that TPAFSO exhibits a high photoluminescence efficiency of 0.52 in a film form and good/balanced carrier injecting properties, as well as an adequate triplet energy (ET) of 2.1 eV to sensitize red phosphor. Hence, solution-processable single-layer green OLEDs using TPAFSO as emitters exhibit a maximum luminous efficiency (LE) of 4.7 cd A−1 and a maximum brightness of 5952 cd m−2 with a low turn-on voltage of 2.5 V, which is superior to the performance of double-layer devices. Furthermore, considering the TPAFSO as a solution-processed host for red emitters, 5% bis(2-(2′-benzothienyl)-pyridinato-N,C3′)iridium(acetylacetonate) (Ir(btp)2(acac))-doped single-layer devices give a maximum quantum yield of 3.9% and a saturated red emission with CIE coordinates of (0.68, 0.32), which are much better than that of Ir(btp)2(acac)-doped poly(N-vinylcarbazole)-2-tert-butylphenyl-5-biphenyl-1,3,4-oxadiazole (PVK-PBD) single-layer devices. Additionally, the red OLEDs using 4-(dicyanomethylene)-2-t-butyl-6-(1,1,7,7-tetramethyljulolidyl-9-enyl)-4Hpyran (DCJTB)-doped TPAFSO as the emitting layer exhibit a maximum LE of 1.8 cd A−1, and can be compared to the performances of DCJTB/Alq3-based multilayer devices via an evaporation process.

We find that manufacturing firms adopt more conservative capital structures in response to the NOx Budget Trading Program (NBP) of 2004, a regional cap-and-trade program aimed at mitigating the NOx emissions of power plants in 11 midwestern and southeastern states in the United States. Our further analysis demonstrates that, because the NBP induces an electricity price shock, it affects manufacturers’ financial decisions by raising their operating leverage and distress risk. We also find that firms respond to the NBP’s adoption heterogeneously: they adjust their financial leverage more dramatically when facing greater electricity intensity, financial-distress threats, or competitive pressure. In addition, firms adapt not only capital structure but also other financial policies in response to the regulation. Overall, our study shows that climate policy risk constitutes an essential consideration in firm financial decisions. It also highlights potential unintended consequences of policy responses to climate change for the corporate sector.

Landmarks are widely used to assist localization of mobile users in indoor environments. Learning a priori unknown or imprecise landmark positions through users’ localization processes can in turn improve their localization performance. In this letter, we develop an analytical framework for landmark learning in localization, in which the positions of the landmarks are continually refined by the inter-landmark measurements from users. We derive the limit and convergence rate of the localization accuracy in asymptotic regimes. Our results characterize the effects of the number of landmarks, the number of inter-landmark measurements, and other non-ideal effects on the localization performance. Theoretical results are validated by simulations and experiments.

This study is about testing the accuracy of the sensor to monitor the seeding parameters of the precision metering device under different seeding speeds and seeding spacings. The purpose is to discover the change law of the sensor's monitoring accuracy of a single seed flow under different seeding speeds and seeding spacings. In particular, it is explored to improve the accuracy of the seeding parameter monitoring sensor under the conditions of high seeding speed and small seeding distance. In this study, three types of sensors were selected for testing, including two infrared optoelectronic sensors and one high-frequency radio wave sensor. The same monitoring system is used to test the monitoring accuracy of the three main parameters of seeding quantity, qualified rate, and missed rate. The test was carried out at five speeds and three spacings gradient levels. The results showed that the three different sensors have similar changes in the parameter monitoring of the seeding quantity relative error, the qualified rate, and the missed rate. When the seeding speed is high and the seeding spacing is small, the change of the sensor monitoring accuracy is very obvious. The significant difference is most obvious when the speed is ≥ 14 km/h and the spacing is ≤ 20 cm. Further analysis found that the frequency of seeds passing through the sensor is the most direct factor that affects the accuracy of sensor monitoring. As the frequency increases, the sensor monitoring accuracy gradually decreases, especially after the frequency reaches 25.92 seeds/s, the sensor monitoring accuracy drops sharply, showing a leaping change. Therefore, improving the accuracy of the sensor's monitoring of the seed passing frequency is of great help to the improvement of the seeding monitoring accuracy under the conditions of high seeding speed and small seeding spacing.

Augmented reality retail applications (ARRAs) have emerged as rapidly developing innovative and futuristic retail innovation used in both physical store and online shops to improve the retail settings and customer experience. So, the objective of this research was to identify predictors of user benefits of ARRA in the retail food chain. By integrating the theory of information system success model, this study proposes a model to investigate the mediating effect of two values: (1) user satisfaction and (2) user continuance intention between quality perspective as explanatory variables (system, service, and information quality) and user benefits as the outcome variable. Both the mediating factors are found positively playing mediating roles among all proposed relationships. This paper provides valuable course of action for retailers and marketers on assessing customers satisfaction and using ARRA to create marketing strategies effectively.

The laser cleaning effect can be affected by many parameters, including laser power, scanning speed, laser repetition rate, and pulse duration, and the cleaning effect with these parameters is investigated. It is found that the cleaning effect is negligible for an infrared high-repetition nanosecond-pulsed laser with repetition rate from 100 to 400 kHz and pulse duration from 58 to 240 ns and is significantly related to the laser power and scanning speed. Moreover, the cleaning thresholds related to laser power and scanning speed for a soil rust layer on ceramic artifacts are measured under the step distance of 281.3 μm. The heat conduction equation and thermal stress equation are used to simulate the cleaning effect with the influence of these parameters, which is in good agreement with the experimental data.

High-energy, high-power laser system for inertial confinement fusion (ICF), such as National Ignition Facility (NIF), is large in size and expensive in construction. The multi-pass amplifier (MA) with the large aperture amplifiers is widely used in high-power laser systems, such as ICF drivers. The systems with MA usually have four features: square beam, single aperture, single pulse and unidirectional propagation, and the expensive preamplifier systems are required to compensate for the limited gain of the main amplifiers. The gain and the extraction efficiency are limited in part by the number of passes that the beam can make through the amplifiers. Besides, the laser system in the multi-pass amplifier should operate at much higher fluence to achieve high extraction efficiency, which results in a technical challenge in the damage of optical components under high-power lasers irradiation. To efficiently extract the stored energy with low injection energy at low laser fluence operation and make the system compact and reliable, a bidirectional ring amplifier (BRA) with twin pulses is proposed and discussed. The structure of the bidirectional ring amplifier is described. The characteristics of the bidirectional ring amplifier on extraction efficiency and output energy capability are simulated and discussed. The simulation results show that an extraction efficiency of 62.3% and the output energy of 13.4 kJ per pulse at the B integral limit can be obtained at low average fluence of 10.3 J/cm2 and the low injection energy of 3.9 mJ in the bidirectional ring amplifier. Compared with the multi-pass amplifier, the bidirectional ring amplifier is more compact and the extraction efficiency is much higher at low laser fluence operation, which is beneficial to reduce the effects of nonlinear phase shift. Furthermore, the preamplifier system for the bidirectional ring amplifier is simple, only a fiber oscillator and a regenerative amplifier can work.

The output performances of a bidirectional ring amplifier with twin pulses are demonstrated. Compared to the extraction efficiency of 32% for single-pulse injection, the extraction efficiency of stored energy for twin-pulse injection with bidirectional propagation is increased to 60%. The maximum output energies of the twin pulses are 347 mJ and 351 mJ, and the output energy of a single pulse is only 373 mJ under the same amplifier operating conditions. The experimental results show that the bidirectional ring amplifier with twin pulses can achieve a higher extraction efficiency of stored energy at a lower operating fluence, and has potential applications in high-power and high-energy laser facilities.

Ultra-Wide Band (UWB) radio is capable of provid- ing sufficient information for high accuracy localization. However, its actual performance is degraded due to the non-line-of-sight (NLOS) propagation. This paper introduces a probabilistic learning approach to mitigate the ranging error and yield uncertainties which correlate with the mitigation results. By combining variational inference with probabilistic neural networks, we propose a new probabilistic deep learning architecture, which can improve the accuracy significantly especially when the training data is limited. Results show that the proposed model can reduce the root mean square error (RMSE) of UWB ranging by 16%∼56% compared with existing support vector machine approach in practical environment.

The ongoing outbreaks of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has led to a worldwide pandemic of Coronavirus Disease (COVID-19) in 2019. Nucleic Acid Tests as the current most prevalent method are able to detect the presence of SARS-CoV-2 from infected patients by comparing target viral genome sequences in high sensitivity and accuracy. Three widely applied nucleic acid methods for clinical and research purpose including RT-PCR tests, LAMP and CRISPR-Cas based detection are introduced firstly, followed by the discussion of Antibody Tests, which are ICG and CL immunoassay tests.These two fields of COVID-19 diagnostic methods exhibit some advantages and drawbacks depending on various clinical settings. Antibody test is supplementary and complementary of other diagnostic methods while Nucleic acid tests are overall effectively and rapidly to diagnose infected patients for immediate treatment and isolation. The combination of these two methods may eventually control the dissemination of COVID-19 pandemic. © 2021 The Authors, published by EDP Sciences.

Corrosion and exciton quenching of commonly used interlayer PEDOT:PSS for OLEDs have been paid great attention, and an effective method is to insert a thin interlayer between PEDOT:PSS and an active layer. Herein, we report an electrochemical method (ECP) to deposit such an interlayer on PEDOT:PSS. Meanwhile, such an interlayer is designed as insoluble and conductive with electronic structures of a wide-bandgap and high triplet state level as well, which are particularly suitable for solution-processed multilayer phosphorescent OLEDs. Accordingly, the molecule SimCP2 was selected as the precursor for electrochemical deposition. The oxidation coupling reactions between the cabazoles in SimCP2 result in a deposition of cross-linked thin film on PEDOT:PSS layer. A solution-processed hyperbranched polymer (HBIr) with fac-tris(2-phenylpyridine)iridium (Ir(ppy)3) as the core and 3,6-carbazole-co-2,8-dioctyldibenzothiophene-S,S-dioxide-3,7-diyl as the branch was used as a phosphorescent active layer to verify the effect of the new interlayer. When the ECP interlayer with an optimal thickness was inserted, the luminance of PhOLEDs device increased from 5000 cd m−2 of the control device to 7368 cd m−2, leading to an enhancement of luminous efficiency (LE) and external quantum efficiency (EQE) from 24.4 cd A−1 and 9.0% of the control device to 32.5 cd A−1 and 12%, respectively. The cross-linked ECP interlayer not only effectively protects the triplet excitons from quenching at the interface between the emitting layer (EML) and PEDOT:PSS, but also blocks the superfluous holes injected and the electrons passed through the EML, which greatly improves device performances. This study paves the way for future applications of ECP interlayers towards highly efficient flexible organic optoelectronic devices.

Paint removal based thermal stress with high repetition pulse is considered in this paper. The temperature distribution of aluminum substrate and paint under laser irradiation is simulated and the thermal stress generated by thermal expansion is calculated. The adhesion force between the paint and the substrate was calculated according to adhesion formula. The conditions for the paint removal can be obtained by comparing the force of thermal stress and adhesion. At the scan speed of 5000 mm/s, the fiber laser with wavelength of 1064 nm, pulse width of 240 ns and frequency of 100 kHz is used to strip red paint from aluminum without any damage. And the stripping effect at the different output power is also taken into account.

The slit spatial filter can be used in high-power laser system. The performance of two-lens slit spatial filter is described and discussed. The laser intensity at the slit edge and the peak intensity of the focal line with different F-numbers and the cut-off frequencies are compared with that of the traditional spatial filter. Simulation results show that the laser intensity at the slit edge and the peak intensity of the focal line are less two orders of magnitude than that of the traditional spatial filter. Besides, the vacuum degree required in the slit spatial filters is about 10-1 Torr, which is less two orders of magnitude than that of the traditional spatial filter.

In this paper, the laser cleaning soil rust layer on the surface of ceramic artifacts by the way of ablation and thermal stress with infrared high-repetition pulse laser is carried out. A cleaning effect can be achieved with laser scanning 10 times at the speed of 480 mm/s and fluence of 795.7747 J/m2 near the ablation threshold. However, the external force is required to make the soil rust layer fallen off. In contrast, a better cleaning effect that the soil rust layer is directly peeled off under the effect of thermal stress without ablation at the contact surface and external force can be observed with the fluence of 1591.5494 J/m2 and laser scanning at 1 time. Furthermore, a two-layer structure model is built to analyze the mechanism of cleaning by thermal stress based on the heat conduction and thermal stress equation. The maximum peeling thermal stress at the contact surface is 2.854×107 N/m2, which is greater than the adhesion stress of 2.050×107 N/m2. This is in agreement with experiments.

The cathode interlayer is of crucial importance for efficient electron injection in inverted polymer light-emitting diodes (PLEDs) to realize high electroluminescence efficiency. Here, a novel photoconductive cathode interlayer based on organic dye-doped ZnO (ZnO:PBI-H) is applied as the cathode buffer layer in PLEDs, and dramatically enhanced device performance is obtained. The photodoping of ZnO may greatly promote the electron injection ability under the device working conditions, which increases the electron-hole recombination efficiency when using P-PPV as the light-emitting material. Thanks to the decreased energy barrier between the cathode interlayer and the light-emitting layer, the turn-on voltage of the PLEDs is obviously reduced when using the photoconductive cathode interlayer. Our results indicate that photodoping of the cathode interlayer is a promising strategy to increase the interlayer performance in light-emitting diodes.

Organic light-emitting diodes (OLEDs) have been extensively studied since the first efficient device based on small molecular luminescent materials was reported by Tang. Organic electroluminescent material, one of the centerpieces of OLEDs, has been the focus of studies by many material scientists. To obtain high luminosity and to keep material costs low, a few remarkable design concepts have been developed. Aggregation-induced emission (AIE) materials were invented to overcome the common fluorescence-quenching problem, and cross-dipole stacking of fluorescent molecules was shown to be an effective method to get high solid-state luminescence. To exceed the limit of internal quantum efficiency of conventional fluorescent materials, phosphorescent materials were successfully applied in highly efficient electroluminescent devices. Most recently, delayed fluorescent materials via reverse-intersystem crossing (RISC) from triplet to singlet and the “hot exciton” materials based on hybridized local and charge-transfer (HLCT) states were developed to be a new generation of low-cost luminescent materials as efficient as phosphorescent materials. In terms of the device-fabrication process, solution-processible small molecular luminescent materials possess the advantages of high purity (vs. polymers) and low procession cost (vs. vacuum deposition), which are garnering them increasing attention. Herein, we review the progress of the development of small-molecule luminescent materials with different design concepts and features, and also briefly examine future development tendencies of luminescent materials.

An insoluble electrochemically cross-linked thin film is successfully applied as an interface layer between PEDOT:PSS and the light emitting layer in solution-processed polymer light-emitting diodes for enhanced device performance.

A novel bidirectional ring amplifier with twin pulses for high-power lasers is proposed, and the performances on output energy capability and extraction efficiency are comprehended with detailed simulation. The results show that an extraction efficiency of 62.3% and the output energy of 13.4 kJ per pulse at the B integral limit can be obtained at low average fluence of 10.3 J/cm2 and the low injection energy of 3.9 mJ in the bidirectional ring amplifier. Compared with the multi-pass amplifier, the bidirectional ring amplifier is more compact and the extraction efficiency is much higher at low injection energy and low laser fluence operation, which is beneficial to simplify the preamplifier system and reduce the effects of nonlinear phase shift.

Aiming for a three-lens slit spatial filtering system with excellent performances in inhibition of pinhole closure, improvement of beam quality, compactness of the system, and lowering the requirement of vacuum, the filtering characteristics and image relay of the slit spatial filter are demonstrated. The results show that the beam quality is greatly improved, and the system has a good property in image relay, which has potential applications in high-power lasers.

Inverted-type polymer light-emitting diodes with Au nanoparticles modified ITO cathode has exhibited improved brightness from 5900 to 15,000 cd m(-2) (1.5-fold enhancement) and enhanced luminous efficiency from 4.4 to 10.5 cd A(-1) (1.4-fold enhancement), when greenish emissive polymer-P-PPV was applied as active layer. Both the experimental and theoretical results show that it is mainly attributed to effective overlapping between local surface plasmon resonance induced by Au nanopartices and excitons quenching region at ZnO/P-PPV interface, which makes originally electrode-quenched excitons emissive and increases excitons efficiency.

Over the past two years, the refugee crisis resulted from the racial conflict, persecution, generalized violence and violations of human rights has forced an enormous number of refugees to flee to Europe. Aiming to address the problem caused by the flow of refugees, we analyzed the actual procedure of their movement and divide it into three major stages. We designed the gathering model, the entering model, the transferring model, even the health and safety model. Finally, we used the models described above to complete our assigned tasks. Also we put forward seven major policy recommendations to the committee. We accompanied every policy with a straightforward explanation so that people without any technical background can easily understand our insights. The main strength of our model is that it can forecast the flow of immigration and provide meaningful suggestions policies for refugees. With the help of modern computing software, we can track the current tendency and make judges efficiently.