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1.
Energy Econ ; 114: 106318, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36124284

RESUMO

The COVID-19 pandemic caused severe economic contraction and paralyzed industrial activity. Despite a growing body of literature on the impacts of COVID-19 mitigation measures, scant evidence currently exists on the impacts of lockdowns on the economic and industrial activities of developing countries. Our study provides an empirical assessment of lockdown measures using 298,354 data points on daily electricity consumption in 396 sub-industries. To infer causal relationships, we employ difference-in-differences models that compare cities with and without lockdown policies and provide quantitative evidence on whether the long-term gain of lockdowns outweighs the short-term loss. The results show that lockdown policies led to a significant short-term drop in electricity consumption of 15.2% relative to the control group. However, the electricity loss under the no-lockdown scenario is 2.6 times larger than that under the strict lockdown scenario within 4 months of the outbreak. Discrepancies in the impacts among industries are identified, and even within the same industry, lockdowns have heterogeneous effects. The impact of lockdowns on small and medium-sized enterprises in developing countries is seriously underestimated, raising concerns about the distributional impact of subsidy measures. This study serves as a crucial reference for the government when facing public health emergencies and shocks to support better policies.

2.
J Environ Manage ; 300: 113721, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34543969

RESUMO

Joint prevention and control of atmospheric pollution (JPCAP) policies play a vital role in alleviating regional pollution. Based on Latent Dirichlet Allocation (LDA) model, we construct two policy strength measures of effectiveness and number, and investigate the effects of policy strength on air pollutant emissions for four types of JPCAP policies. The results show that the effects of economic incentive policy tools and supporting policy tools on emission reduction deviate significantly from policy preferences. Economic incentive policy tools are the most effective in promoting emission reductions in SO2, NOx and dust, but their effectiveness are the lowest in reality. Supporting policy tools, with the highest strength, have little effect on emission reduction. Command-control policies and persuasion policies are both relatively high in quantity and effectiveness. In addition, policy strength plays a more important role in reducing air pollutants in key regions than in non-key regions. JPCAP policies have gradually changed from a single policy tool to multiple policy tools, and the government shifted its attention to improving the legal effectiveness of policies after 2015. Finally, we propose some policy implications to optimize JPCAP policies and address regional air pollution problem.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Poluição do Ar/prevenção & controle , China , Monitoramento Ambiental , Material Particulado/análise , Políticas
3.
Nat Commun ; 15(1): 6041, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39019903

RESUMO

Electrification plays a crucial role in deep decarbonization. However, electrification and power infrastructure can cause mutual challenges. We use nationwide power outage and electric vehicle adoption data in China to provide empirical evidence on how power infrastructure failures can deter electrification. We find that when the number of power outages per district increases by 1 in a given month, the number of new electric vehicles adopted per month decreases by 0.99%. A doubling of power outages in one year on average across the nation can create a depressed adoption rate for up to a decade, implying a decline of more than $ 31.3 million per year in carbon reduction benefits from electric vehicle adoptions. This paper adds to the policy discussion of the costs of increased power outages due to extreme weather and natural disasters, and the urgency for policy to address this issue to facilitate wide adoption of electrification.

4.
iScience ; : 107177, 2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37366395

RESUMO

Pandemics such as COVID-19 threaten income growth by disrupting productive activities for households, especially those who have just escaped from poverty. We provide empirical evidence on how pandemic disproportionately threatens the rural productive livelihood based on 48 months of household production electricity consumption data. The results show that after COVID-19, the productive livelihood activities of 51.11% households who have just overcome poverty have returned to the level before poverty alleviation. Their productive livelihood activities dropped by 21.81% on average during the national COVID-19 epidemic and by 40.57% during the regional epidemic. The households with lower income, lower level of education and less labor force even suffer more. We estimate 3.74% decline in income owing to the decrease in productive activities, resulting in 5.41% of households potentially falling back into poverty. This study provides an important reference for countries being at risk of returning to poverty after pandemic.

5.
Nat Commun ; 14(1): 6202, 2023 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-37794008

RESUMO

The incentive-based emergency demand response measure serves as an important regulatory tool during energy system operations. However, whether people will sacrifice comfort to respond to it during heatwave and what the effect on heat vulnerable populations will be are still unclear. A large-scale emergency demand response pilot involving 205,129 households was conducted in southwestern China during continuous extreme high temperatures in summer. We found that the incentive-based emergency demand response causes a statistically significant decline in electricity use with no additional financial burden on vulnerable groups. The electricity conservation potential of urban households was higher than that of rural households. Households with children did not respond to the emergency demand response, while the response of households with elderly individuals proved to be more positive. The repeated and frequent implementation of this policy did not result in an attenuation of the regulatory effect. This research can serve as a reference for countries with similar regulated power markets.


Assuntos
Temperatura Alta , Motivação , Criança , Humanos , Idoso , Estações do Ano , China , População Rural
6.
Nat Commun ; 13(1): 5772, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-36182940

RESUMO

Energy efficiency improvement is often hindered by the energy efficiency gap. This paper examines the effect of short-run temperature fluctuations on the Energy Star air conditioner purchases in the United States from 2006 to 2019 using transaction-level data. Results show that the probability of purchasing an Energy Star air conditioner increases as the weekly temperature before the transaction deviates from 20-22 °C. A larger response is related to fewer cooling degree days in the previous years, higher electricity prices/income/educational levels/age/rate of owners, more common use of electricity, and stronger concern about climate change. 1 °C increase and decrease from 21 °C would lead to a reduction of total energy expenditure by 35.46 and 17.73 million dollars nationwide (0.13% and 0.06% of the annual total energy expenditure on air conditioning), respectively. Our findings have important policy implications for demand-end interventions to incorporate the potential impact of the ambient physical environment.


Assuntos
Conservação de Recursos Energéticos , Tempo (Meteorologia) , Mudança Climática , Eficiência , Temperatura , Estados Unidos
7.
Nat Commun ; 13(1): 2456, 2022 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-35508551

RESUMO

Income-based energy poverty metrics ignore people's behavior patterns, particularly reducing energy consumption to limit financial stress. We investigate energy-limiting behavior in low-income households using a residential electricity consumption dataset. We first determine the outdoor temperature at which households start using cooling systems, the inflection temperature. Our relative energy poverty metric, the energy equity gap, is defined as the difference in the inflection temperatures between low and high-income groups. In our study region, we estimate the energy equity gap to be between 4.7-7.5 °F (2.6-4.2 °C). Within a sample of 4577 households, we found 86 energy-poor and 214 energy-insecure households. In contrast, the income-based energy poverty metric, energy burden (10% threshold), identified 141 households as energy-insecure. Only three households overlap between our energy equity gap and the income-based measure. Thus, the energy equity gap reveals a hidden but complementary aspect of energy poverty and insecurity.


Assuntos
Renda , Pobreza , Características da Família , Abastecimento de Alimentos , Humanos
8.
iScience ; 25(6): 104352, 2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35601916

RESUMO

This study provides an empirical assessment of how adopting battery storage units can change the electricity consumption patterns of PV consumers using individual-consumer-level hourly smart meter data in Arizona, United States. We find that on average after adding batteries, PV consumers use more solar electricity to power their houses and send less solar electricity back to the grid. In addition, adding battery storage reduces electricity needed from the grid during system peak hours, helping utilities better flatten the load curves. Most importantly, we find a large degree of heterogeneity in the changes in electricity consumption patterns due to adopting battery storage that are not consistent with engineering or economic principles such as those not maximizing consumers' economic benefits. Such heterogeneous changes imply that utilities and policymakers need to further study the underlying behavioral reasons in order to maximize the social benefits of battery storage and PV co-adoption.

9.
iScience ; 25(11): 105456, 2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36388983

RESUMO

Energy demand-side management is essential for deep decarbonization. However, while we target people as discrete and isolated individuals, we ignore the fact that energy consumption occurs in intricate webs of pre-existing social relations. This study examines an emergency demand response (EDR) program in China involving more than 180,000 households based on relations with family members, communities, and identity. The results indicate that the existence of social relations can promote energy conservation behavior and there is a large degree of heterogeneity. Targeted relations, such as single-living residents, small-scale households, city dweller etc., show greater electricity savings with 12.35% increase in overall effect, which benefit when demographics change in the next few decades. Such heterogeneous changes put forward the pressing need for policymakers to focus on social relations as a unit in future intervention designs to decarbonize the energy system.

10.
iScience ; 24(11): 103231, 2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34642653

RESUMO

The COVID-19 pandemic has exacerbated energy insecurity and economic hardship among vulnerable populations. This paper provides robust empirical evidence of the degree to which COVID-19 mitigation measures, especially the mandates of school closure and limiting business operations, have impacted electricity consumption behavior in low-income and ethnic minority groups in the United States. We use a regression discontinuity design applied to individual-consumer-level high-frequency smart meter data in Arizona and Illinois to highlight the disparities in mitigation measure impacts. We find that the mandates of school closures and limiting business operations increase residential electricity consumption by 4-5%, but reduce commercial electricity consumption by 5-8%. Considerable heterogeneity is observed across income and race: low-income and ethnic-minority populations experience a larger electricity consumption increase, reflecting the disproportionate impact of COVID-19 on electricity insecurity in the residential sector. Policies that address energy insecurity, especially during the pandemic, become essentially important.

11.
Nat Commun ; 11(1): 1969, 2020 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-32327649

RESUMO

Since 2013, China has implemented a large-scale initiative to systematically deploy solar photovoltaic (PV) projects to alleviate poverty in rural areas. To provide new understanding of China's targeted poverty alleviation strategy, we use a panel dataset of 211 pilot counties that received targeted PV investments from 2013 to 2016, and find that the PV poverty alleviation pilot policy increases per-capita disposable income in a county by approximately 7%-8%. The effect of PV investment is positive and significant in the year of policy implementation and the effect is more than twice as high in the subsequent two to three years. The PV poverty alleviation effect is stronger in poorer regions, particularly in Eastern China. Our results are robust to alternative specifications and variable definitions. We propose several policy recommendations to sustain progress in China's efforts to deploy PV for poverty alleviation.

14.
J Chromatogr A ; 1136(1): 99-105, 2006 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-17054968

RESUMO

A solid-phase extraction (SPE)/GC-MS method using multiwalled carbon nanotubes (MWCNTs) was developed for the determination of four benzodiazepine residues including diazepam, estazolam, alprazolam and triazolam in pork. The analytes were extracted by ultrasonic assistant extraction using acetonitrile, concentrated and purified by MWCNTs packed cartridge, and determined by GC-MS. Ultrasonic extraction conditions, which included temperature, time, power, and solvent volume, were optimized. Comparative studies showed that MWCNTs were superior to C18 for the adsorption of drugs. Parameters influencing SPE efficiency, such as sample amounts, variety and volume of the eluent, were also optimized. Electron ionization (EI) operating in time program-selected ion monitoring mode (SIM) was used for GC-MS identification. The analytes were quantified with external standard calibration curve method. Lower limit of detection and quantification was obtained by the new method. Linear calibration curves were obtained in the concentration range from 10 ng/mL to 500 ng/mL for diazepam and from 20 ng/mL to 1000 ng/mL for estazolam, alprazolam and triazolam with calibration coefficients of 0.99 and above. The average recoveries for the four benzodiazepines spiked in pork were 75% to 104% and their relative standard deviations were between 1.3% and 10%. The limits of detection were 2 microg/kg for diazepam and 5 microg/kg for estazolam, alprazolam and triazolam in pork, respectively.


Assuntos
Benzodiazepinas/análise , Carbono/química , Resíduos de Drogas/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Produtos da Carne/análise , Nanoestruturas , Adsorção , Animais , Calibragem , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Suínos
15.
Artigo em Inglês | MEDLINE | ID: mdl-16844435

RESUMO

A new method was developed for the rapid extraction and unequivocal determination of barbital, amobarbital and phenobarbital residues in pork. The isolation of the analytes from pork samples was accomplished by utilizing an accelerated solvent extractor ASE 300. The procedure was automatically carried out in series for fat removing and extraction, respectively with n-hexane and acetonitrile pressurized constantly at 10.3 MPa for 30 min. After evaporation, the extracts were cleaned up on a C(18) solid phase extraction (SPE) cartridge and the barbiturates were eluted with hexane-ethyl acetate (7:3), evaporated on a rotary evaporator and derivatized with CH(3)I. The methylated barbiturates were separated on a HP-5MS capillary column and detected with a mass detector. Electron impact ion source (EI) operating in time program-selected ion monitoring mode (SIM) was used for identification and external standard method was used for quantification. Good linearity was obtained in the range from 0.5 microg/kg to 25 microg/kg. Average recoveries of the three barbiturates spiked in pork ranged from 84.0% to 103.0%, with relative standard deviations from 1.6% to 12%. The limit of detection (LOD) was 0.5 microg/kg for the three barbiturates (S/N>or=3). The quantification limit (LOQ) was 1 microg/kg for the three barbiturates (S/N>or=10).


Assuntos
Barbitúricos/análise , Resíduos de Drogas/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Produtos da Carne/análise , Animais , Calibragem , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Solventes , Suínos
16.
Opt Express ; 13(12): 4699-707, 2005 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-19495386

RESUMO

An optically triggered liquid crystal infiltrated Q-switched photonic crystal laser is demonstrated. A photonic crystal laser cavity was designed and fabricated to support two orthogonally polarized high-Q cavity modes after liquid crystal infiltration. By controlling the liquid crystal orientation via a layer of photoaddressable polymer and a writing laser, the photonic crystal lasing mode can be reversibly switched between the two modes which also switches the laser's emission polarization and wavelength. The creation of the Q-switched laser demonstrates the benefits of customizing photonic crystal cavities to maximally synergize with an infiltrated material and illustrates the potential of integrating semiconductor nanophotonics with optical materials.

17.
J Chromatogr A ; 1074(1-2): 1-7, 2005 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-15941032

RESUMO

A method for determination of thyreostatic residues in animal tissues by matrix solid-phase dispersion (MSPD) and gas chromatography-mass spectrometry in selected ion detection mode was developed. Thyreostatic compounds in different matrices were extracted and purified by combination of MSPD and subsequent solid-phase extraction. Silica gel was selected as the solid support of both procedures and the conditions of the procedures were optimized. Thyreostats were derivatized with pentafluorobenzylbromide (PFBBr) in strong basic medium and then with N-methyl-N-(trimethylsilyl)-trifluoroacetamide (MSTFA), which can improve the yields of derivatization for thyreostats, the repeatability, and therefore the limits of detection (LOD) of thyreostats. The limits of detection reached 10 microg/kg (2-thiouracil, 6-methyl-2-thiouracil and 6-propyl-2-thiouracil), 20 microg/kg (6-phenyl-2-thiouracil) and 50 microg/kg (tapazole) with high recoveries (more than 70% for most of thyreostats) and relative standard deviations between 4.5% and 8.7%.


Assuntos
Antitireóideos/análise , Fluoracetatos , Acetamidas , Animais , Antitireóideos/isolamento & purificação , Fluorbenzenos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Metimazol/isolamento & purificação , Metiltiouracila/isolamento & purificação , Propiltiouracila/isolamento & purificação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Sílica Gel , Dióxido de Silício , Suínos , Tiouracila/isolamento & purificação , Compostos de Trimetilsilil
18.
Anal Chim Acta ; 586(1-2): 399-406, 2007 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-17386740

RESUMO

A new method was developed for the rapid screening and confirmation analysis of barbital, amobarbital and phenobarbital residues in pork by gas chromatography-tandem mass spectrometry (GC/MS/MS) with ion trap MSD. The residual barbiturates in pork were extracted by ultrasonic extraction, cleaned up on a multiwalled carbon nanotubes (MWCNTs) packed solid phase extraction (SPE) cartridge and applied acetone-ethyl acetate (3:7, v/v) mixture as eluting solvent and derivatized with CH3I under microwave irradiation. The methylated barbiturates were separated on a TR-5MS capillary column and detected with an ion trap mass detector. Electron impact ion source (EI) operating MS/MS mode was adopted for identification and external standard method was employed for quantification. One precursor ion m/z 169 was selected for analysis of barbital and amobarbital and m/z 232 was selected for phenobarbital. The product ions were obtained under 1.0 V excitation voltage. Good linearities (linear coefficient R > 0.99) were obtained at the range of 0.5-50 microg kg(-1). Limit of detection (LOD) of barbital was 0.2 microg kg(-1) and that of amobarbital and phenobarbital were both 0.1 microg kg(-1) (S/N > or = 3). Limit of quantification (LOQ) was 0.5 microg kg(-1) for three barbiturates (S/N > or = 10). Satisfying recoveries ranging from 75% to 96% of the three barbiturates spiked in pork were obtained, with relative standard deviations (R.S.D.) in the range of 2.1-7.8%.


Assuntos
Barbitúricos/análise , Cromatografia por Troca Iônica/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Micro-Ondas , Nanotubos de Carbono/análise , Extração em Fase Sólida/métodos , Adsorção , Amobarbital/análise , Animais , Barbital/análise , Calibragem , Elétrons , Íons , Suínos , Ultrassom
19.
Se Pu ; 24(1): 14-8, 2006 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-16827302

RESUMO

A method was developed for the simultaneous determination of chloramphenicol (CAP), thiamphenicol (TAP), and florfenicol (FF) residues in animal tissues using gas chromatography/mass spectrometry (GC/MS) with chemical ionization source in negative mode. The homogenized samples were extracted with ethyl acetate and the extracts were partitioned with n-hexane to remove lipids. Further cleanup was performed on a florisil cartridge and the purified samples were derivatized with Sylon BFT [N, O-bis (trimethylsilyl) trifluoroacetamide (BSTFA)-trimethylchlorosilane (TMCS), 99: 1, v/v] in toluene. Meta-nitrochloramphenicol (m-CAP) was used as the internal standard for the determination. Selected ion monitoring (SIM) was used for detection, ions were chosen, respectively, for the monitoring at m/z 432, 466, 468, 470 for m-CAP, m/z 376, 378, 466, 468 for CAP, m/z 409, 411, 499, 501 for TAP, and m/z 339, 341, 429, 431 for FF. Quantitative ions were selected at m/z 466 for CAP and m-CAP, at m/z 339 for FF and at m/z 409 for TAP. The detection limits were 0.03 microg/kg for CAP, 0.2 microg/kg for FF and TAP. The correlation coefficients were above 0.99 for the calibration curves of the medicines. The linear ranges were 0.1 - 8.0 microg/kg for CAP and 0.2 - 4.0 microg/kg for FF and TAP. The reproducibilities of the compounds within a batch were 5.5%, 10.4%, and 8.8% for CAP, FF, and TAP respectively, while the corresponding values between the batches were 7.4%, 20.7%, and 19.1%. The recoveries were 80.0% - 111.5%, and the relative standard deviations were 1.2% - 15.4%. The method is applicable for detection of the residues in animal derived food, such as pork, poultry and aquatic products.


Assuntos
Cloranfenicol/análise , Tianfenicol/análogos & derivados , Tianfenicol/análise , Animais , Cromatografia Gasosa-Espectrometria de Massas , Hexanos , Limite de Detecção , Suínos
20.
Se Pu ; 24(4): 347-50, 2006 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-17017157

RESUMO

A rapid, sensitive and accurate method has been developed for the determination of seventeen 2, 3, 7, 8-substituted congeners of polychlorinated dibenzo-p-dioxins and dibenzo-furans (PCDD/Fs) in sediment using isotope dilution high resolution gas chromatography/high resolution mass spectrometry (HRGC/HRMS). Dibenzo-p-dioxins and dibenzo-furans were extracted from samples by accelerated solvent extraction (ASE) and then purified by fluid management systems (FMS) with silica column, alumina column and carbon column. Confirmation and quantitative analysis at pg/g level of PCDD/Fs were performed by HRGC/HRMS using voltage selective ion record (VSIR) mode. Recoveries of fifteen isotopically labeled compound solutions (LCS) and the precision and recovery standards (PAR) were found to be in the range of 49.8% -85.3% and 93.2% - 113.8%, respectively. The detection limits of the method for both 2, 3, 7, 8-tetrachloro-dibenzo-furan (TCDF) and 2, 3, 7, 8-tetrachloro-dibenzo-p-dioxin (TCDD) were determined to be 0.1 pg/g. This method not only meets the requirements of international standards, but also shortens analysis time from 2 weeks to 2 days.


Assuntos
Benzofuranos/análise , Cromatografia Gasosa/métodos , Espectrometria de Massas/métodos , Óleos de Plantas/química , Dibenzodioxinas Policloradas/análogos & derivados , Benzofuranos/química , Dibenzofuranos Policlorados , Dioxinas/química , Furanos/análise , Furanos/química , Limite de Detecção , Dibenzodioxinas Policloradas/análise , Dibenzodioxinas Policloradas/química
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