Influence of static disorder of charge transfer state on voltage loss in organic photovoltaics

AbstractSpectroscopic measurements of charge transfer (CT) states provide valuable insight into the voltage losses in organic photovoltaics (OPVs). Correct interpretation of CT-state spectra depends on knowledge of the underlying broadening mechanisms, and the relative importance of molecular vibrational broadening and variations in the CT-state energy (static disorder). Here, we present a physical model, that obeys the principle of detailed balance between photon absorption and emission, of the impact of CT-state static disorder on voltage losses in OPVs. We demonstrate that neglect of CT-state disorder in the analysis of spectra may lead to incorrect estimation of voltage losses in OPV devices. We show, using measurements of polymer:non-fullerene blends of different composition, how our model can be used to infer variations in CT-state energy distribution that result from variations in film microstructure. This work highlights the potential impact of static disorder on the characteristics of disordered organic blend devices.

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Charge-transfer state energy determines open-circuit voltage in organic photovoltaics

SPIE Newsroom ◽

10.1117/2.1201309.005006 ◽

2013 ◽

Cited By ~ 1

Author(s):

Kenneth Graham ◽

Aram Amassian ◽

Ruipeng Lee ◽

Guy Olivier Ngongang Ndjawa ◽

Patrick Erwin ◽

...

Keyword(s):

Charge Transfer ◽

Organic Photovoltaics ◽

State Energy ◽

Open Circuit Voltage ◽

Open Circuit ◽

Charge Transfer State ◽

Transfer State

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Impact of temperature and relative humidity on the transmission of COVID-19: a modelling study in China and the United States

BMJ Open ◽

10.1136/bmjopen-2020-043863 ◽

2021 ◽

Vol 11 (2) ◽

pp. e043863

Author(s):

Jingyuan Wang ◽

Ke Tang ◽

Kai Feng ◽

Xin Lin ◽

Weifeng Lv ◽

...

Keyword(s):

Regression Analysis ◽

Relative Humidity ◽

Human Mobility ◽

The United States ◽

Reproductive Number ◽

Cross Sectional ◽

The Usa ◽

Higher Temperature ◽

Potential Impact ◽

The Impact

ObjectivesWe aim to assess the impact of temperature and relative humidity on the transmission of COVID-19 across communities after accounting for community-level factors such as demographics, socioeconomic status and human mobility status.DesignA retrospective cross-sectional regression analysis via the Fama-MacBeth procedure is adopted.SettingWe use the data for COVID-19 daily symptom-onset cases for 100 Chinese cities and COVID-19 daily confirmed cases for 1005 US counties.ParticipantsA total of 69 498 cases in China and 740 843 cases in the USA are used for calculating the effective reproductive numbers.Primary outcome measuresRegression analysis of the impact of temperature and relative humidity on the effective reproductive number (R value).ResultsStatistically significant negative correlations are found between temperature/relative humidity and the effective reproductive number (R value) in both China and the USA.ConclusionsHigher temperature and higher relative humidity potentially suppress the transmission of COVID-19. Specifically, an increase in temperature by 1°C is associated with a reduction in the R value of COVID-19 by 0.026 (95% CI (−0.0395 to −0.0125)) in China and by 0.020 (95% CI (−0.0311 to −0.0096)) in the USA; an increase in relative humidity by 1% is associated with a reduction in the R value by 0.0076 (95% CI (−0.0108 to −0.0045)) in China and by 0.0080 (95% CI (−0.0150 to −0.0010)) in the USA. Therefore, the potential impact of temperature/relative humidity on the effective reproductive number alone is not strong enough to stop the pandemic.

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Using syndromic measures of mortality to capture the dynamics of COVID-19 in Java, Indonesia, in the context of vaccination rollout

BMC Medicine ◽

10.1186/s12916-021-02016-2 ◽

2021 ◽

Vol 19 (1) ◽

Author(s):

Bimandra A. Djaafara ◽

Charles Whittaker ◽

Oliver J. Watson ◽

Robert Verity ◽

Nicholas F. Brazeau ◽

...

Keyword(s):

Rural Areas ◽

Vaccination Campaign ◽

Control Measures ◽

Additional Insight ◽

Short Term ◽

If Current ◽

Vaccine Impact ◽

Potential Impact ◽

The Impact ◽

Insight Into

Abstract Background As in many countries, quantifying COVID-19 spread in Indonesia remains challenging due to testing limitations. In Java, non-pharmaceutical interventions (NPIs) were implemented throughout 2020. However, as a vaccination campaign launches, cases and deaths are rising across the island. Methods We used modelling to explore the extent to which data on burials in Jakarta using strict COVID-19 protocols (C19P) provide additional insight into the transmissibility of the disease, epidemic trajectory, and the impact of NPIs. We assess how implementation of NPIs in early 2021 will shape the epidemic during the period of likely vaccine rollout. Results C19P burial data in Jakarta suggest a death toll approximately 3.3 times higher than reported. Transmission estimates using these data suggest earlier, larger, and more sustained impact of NPIs. Measures to reduce sub-national spread, particularly during Ramadan, substantially mitigated spread to more vulnerable rural areas. Given current trajectory, daily cases and deaths are likely to increase in most regions as the vaccine is rolled out. Transmission may peak in early 2021 in Jakarta if current levels of control are maintained. However, relaxation of control measures is likely to lead to a subsequent resurgence in the absence of an effective vaccination campaign. Conclusions Syndromic measures of mortality provide a more complete picture of COVID-19 severity upon which to base decision-making. The high potential impact of the vaccine in Java is attributable to reductions in transmission to date and dependent on these being maintained. Increases in control in the relatively short-term will likely yield large, synergistic increases in vaccine impact.

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The impact of social norms on cross-state energy regime changes

Energy Policy ◽

10.1016/j.enpol.2021.112257 ◽

2021 ◽

Vol 154 ◽

pp. 112257

Author(s):

Faraz Farhidi ◽

Vahid Khiabani

Keyword(s):

Social Norms ◽

State Energy ◽

Regime Changes ◽

Energy Regime ◽

The Impact

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Detecting Convergence Trends among EU Universities

Economies ◽

10.3390/economies9020042 ◽

2021 ◽

Vol 9 (2) ◽

pp. 42

Author(s):

Maria Adamakou ◽

Dimitris Kallioras ◽

George Petrakos

Keyword(s):

Methodological Approach ◽

Basic Research ◽

Valuable Insight ◽

Traditional Role ◽

University Ranking ◽

Convergence Clubs ◽

Development Processes ◽

The Impact ◽

The Empirical Analysis ◽

Insight Into

Universities are emerging growth determinants. This is so as, in addition to the fulfillment of their traditional role in teaching and (basic) research, universities, as aptly described within the helix framework, are expected to engage in regional development processes. The paper aims to detect trends of convergence among EU universities in terms of performance. To the best of our knowledge, this topic has not hitherto been examined. The empirical analysis of the paper covers the period 2014–2021, utilizes data obtained from URAP (University Ranking by Academic Performance), and employs the methodological approach of convergence clubs. The findings of the paper provide valuable insight into both theory and policy-making. We conclude that despite the unification of EU educational space, trends of divergence among EU universities are still present, and notable divisions still remain. Consequently, this indicates that the impact of EU universities on the formation of spatial disparities across EU space is not neutral.

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China’s Investments in Germany and the Impact of the COVID-19 Pandemic

Intereconomics ◽

10.1007/s10272-021-0962-0 ◽

2021 ◽

Vol 56 (2) ◽

pp. 113-119

Author(s):

Xinming Xia ◽

Wan-Hsin Liu

Keyword(s):

Large Scale ◽

Know How ◽

Advanced Technologies ◽

The Future ◽

Potential Impact ◽

Chinese State ◽

The Impact ◽

Gain Access ◽

Over Time

AbstractThis paper analyses how China’s investments in Germany have developed over time and the potential impact of the COVID-19 pandemic in this regard, based on four different datasets, including our own survey in mid-2020. Our analysis shows that Germany is currently one of the most attractive investment destinations for Chinese investors. Chinese state-owned enterprises have played an important role as investors in Germany — particularly in large-scale projects. The COVID-19 pandemic has had some negative but rather temporary effects on Chinese investments in Germany. Germany is expected to stay attractive to Chinese investors who seek to gain access to advanced technologies and know-how in the future.

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The potentially hazardous NEA 2001 BB16

Open Astronomy ◽

10.1515/astro-2019-0016 ◽

2019 ◽

Vol 28 (1) ◽

pp. 180-190

Author(s):

Ireneusz Wlodarczyk

Keyword(s):

Mean Value ◽

Optical Observations ◽

Uniform Sampling ◽

The Earth ◽

22Nd Century ◽

Lyapunov Time ◽

Gravitational Model ◽

Calculated Probability ◽

Potential Impact ◽

The Impact

AbstractWe computed the impact solutions of the potentially dangerous Near Earth Asteroid (NEA) 2001 BB16 based on 47 optical observations from January 20.08316 UTC, 2001, through February 09.15740 UTC, 2016, and one radar observation from January 19.90347 UTC, 2016. We used two methods to sample the starting Line of Variation (LOV). First method, called thereafter LOV1, with the uniform sampling of the LOV parameter, out to LOV = 5 computing 3000 virtual asteroids (VAs) on both sides of the LOV, which gives 6001 VAs and propagated their orbits to JD2525000.5 TDT=February 12, 2201. We computed the non-gravitational parameterA2=(34.55±7.38)·10–14 au/d2 for nominal orbit of 2001 BB16 and possible impacts with the Earth until 2201. For potential impact in 2195 we find A2=20.0·10−14 au/d2. With a positive value of A2, 2001 BB16 can be prograde rotator. Moreover, we computed Lyapunov Time (LT) for 2001 BB16, which for all VAs, has a mean value of about 25 y. We showed that impact solutions, including the calculated probability of a possible collision of a 2001 BB16 asteroid with the Earth depends on how to calculate and take into account the appropriate gravitational model, including the number of perturbing massive asteroids. In some complicated cases, it may depend also on the number of clones calculated for a given sigma LOV1. The second method of computing the impact solutions, called thereafter LOV2, is based on a non-uniformly sampling of the LOV. We showed that different methods of sampling the LOV can give different impact solutions, but all computed dates of possible impacts of the asteroid 2001 BB16 with the Earth occur in accordance at the end of the 22nd century.

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The impact of Sosnowsky’s Hogweed on feeding guilds of birds

Journal of Ornithology ◽

10.1007/s10336-021-01898-6 ◽

2021 ◽

Author(s):

Emilia Grzędzicka ◽

Jiří Reif

Keyword(s):

Negative Impact ◽

Bird Community ◽

Plant Invasions ◽

Bird Communities ◽

Feeding Guilds ◽

Guild Structure ◽

Feeding Guild ◽

Potential Impact ◽

Underlying Mechanisms ◽

The Impact

AbstractPlant invasions alter bird community composition worldwide, but the underlying mechanisms still require exploration. The investigation of feeding guild structure of bird communities can be informative in respect to the potential impact of invasion features on the availability of food for birds. For this purpose, we focused on determining the influence of the invasive Sosnowsky’s Hogweed Heracleum sosnowskyi on the abundance of birds from various feeding guilds. In spring and summer 2019, birds were counted three times on 52 pairs of sites (control + Heracleum) in southern Poland, at various stages of Sosnowsky’s Hogweed development (i.e. sprouting, full growth and flowering, all corresponding to respective bird counts). We have shown that the presence of invader negatively affected the abundance of birds from all feeding guilds. However, a closer examination of the invaded sites uncovered that responses of particular guilds differed in respect to development stages expressed by a set of characteristics of the invader. Ground and herb insectivores were more common on plots with a higher number of the invader, while the abundance of bush and tree insectivores was negatively correlated with hogweeds’ height. Granivores were not affected by the invader’s features, while the abundance of omnivores was negatively related to the number of flowering hogweeds. Besides showing the general negative impact of the invader on different feeding guilds, our research has shown that certain aspects of Sosnowsky’s Hogweed invasion may support or depress occurrence of different birds on invaded plots. Knowledge of these aspects may facilitate our capacity for coping with challenges the invasive plants put in front of bird conservationists.

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Restraining Surface Charge Accumulation and Enhancing Surface Flashover Voltage through Dielectric Coating

Coatings ◽

10.3390/coatings11070750 ◽

2021 ◽

Vol 11 (7) ◽

pp. 750

Author(s):

Jixing Sun ◽

Sibo Song ◽

Xiyu Li ◽

Yunlong Lv ◽

Jiayi Ren ◽

...

Keyword(s):

Charge Transfer ◽

Electric Field ◽

Electric Fields ◽

Transition Process ◽

Metallic Particle ◽

Particle Charging ◽

Insulating Surfaces ◽

Surface Flashover ◽

Charging Time ◽

The Impact

A conductive metallic particle in a gas-insulated metal-enclosed system can charge through conduction or induction and move between electrodes or on insulating surfaces, which may lead to breakdown and flashover. The charge on the metallic particle and the charging time vary depending on the spatial electric field intensity, the particle shape, and the electrode surface coating. The charged metallic particle can move between the electrodes under the influence of the spatial electric field, and it can discharge and become electrically conductive when colliding with the electrodes, thus changing its charge. This process and its factors are mainly affected by the coating condition of the colliding electrode. In addition, the interface characteristics affect the particle when it is near the insulator. The charge transition process also changes due to the electric field strength and the particle charging state. This paper explores the impact of the coating material on particle charging characteristics, movement, and discharge. Particle charging, movement, and charge transfer in DC, AC, and superimposed electric fields are summarized. Furthermore, the effects of conductive particles on discharge characteristics are compared between coated and bare electrodes. The reviewed studies demonstrate that the coating can effectively reduce particle charge and thus the probability of discharge. The presented research results can provide theoretical support and data for studying charge transfer theory and design optimization in a gas-insulated system.

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‘Protecting Life in Global Health Assistance’? Towards a framework for assessing the health systems impact of the expanded Global Gag Rule

BMJ Global Health ◽

10.1136/bmjgh-2019-001786 ◽

2019 ◽

Vol 4 (5) ◽

pp. e001786 ◽

Cited By ~ 4

Author(s):

Marta Schaaf ◽

Emily Maistrellis ◽

Hana Thomas ◽

Bergen Cooper

Keyword(s):

Global Health ◽

Mexico City ◽

Health Systems ◽

Grey Literature ◽

Policy Changes ◽

Us Government ◽

Potential Impact ◽

City Policy ◽

The Impact ◽

Initial Research

During his first week in office, US President Donald J Trump issued a presidential memorandum to reinstate and broaden the reach of the Mexico City policy. The Mexico City policy (which was in place from 1985–1993, 1999–2000 and 2001–2009) barred foreign non-governmental organisations (NGOs) that received US government family planning (FP) assistance from using US funds or their own funds for performing, providing counselling, referring or advocating for safe abortions as a method of FP. The renamed policy, Protecting Life in Global Health Assistance (PLGHA), expands the Mexico City policy by applying it to most US global health assistance. Thus, foreign NGOs receiving US global health assistance of nearly any type must agree to the policy, regardless of whether they work in reproductive health. This article summarises academic and grey literature on the impact of previous iterations of the Mexico City policy, and initial research on impacts of the expanded policy. It builds on this analysis to propose a hypothesis regarding the potential impact of PLGHA on health systems. Because PLGHA applies to much more funding than it did in its previous iterations, and because health services have generally become more integrated in the past decade, we hypothesise that the health systems impacts of PLGHA could be significant. We present this hypothesis as a tool that may be useful to others’ and to our own research on the impact of PLGHA and similar exogenous overseas development assistance policy changes.

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