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1.
Environ Sci Pollut Res Int ; 30(43): 97025-97039, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37587396

RESUMO

Climate change adaptation technologies (CCATs) have become increasingly important for farmers as they face the challenges of climate change and natural disasters. Despite this, many rural areas still rely on traditional agricultural techniques. To promote the adoption of CCATs in agriculture, it is necessary to explore the incentives and conditions for the effectiveness of the policy. We develop an evolutionary game model to analyze the behavior of local governments and farmers in promoting CCATs. Our findings indicate that, under certain conditions, the promotion of CCATs can achieve equilibrium. The incentive for farmers to adopt CCATs increases within a certain range when local governments provide risk subsidies and cost sharing. When subsidies are too high, however, local governments may choose not to promote CCATs, which reduces the incentives for farmers to adopt them. Publicity is also an important factor in promoting CCATs. Our study provides insight into the development of policies aimed at promoting CCATs in agriculture.


Assuntos
Mudança Climática , Motivação , Agricultura , Tecnologia , Aclimatação
2.
Sci Total Environ ; 896: 165200, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37400020

RESUMO

Microalgae have been recognized as emerging cell factories due to the high value-added bio-products. However, the balance between algal growth and the accumulation of metabolites is always the main contradiction in algal biomass production. Hence, the security and effectiveness of regulating microalgal growth and metabolism simultaneously have drawn substantial attention. Since the correspondence between microalgal growth and reactive oxygen species (ROS) level has been confirmed, improving its growth under oxidative stress and promoting biomass accumulation under non-oxidative stress by exogenous mitigators is feasible. This paper first introduced ROS generation in microalgae and described the effects of different abiotic stresses on the physiological and biochemical status of microalgae from these aspects associated with growth, cell morphology and structure, and antioxidant system. Secondly, the role of exogenous mitigators with different mechanisms in alleviating abiotic stress was concluded. Finally, the possibility of exogenous antioxidants regulating microalgal growth and improving the accumulation of specific products under non-stress conditions was discussed.


Assuntos
Microalgas , Espécies Reativas de Oxigênio/metabolismo , Microalgas/metabolismo , Biomassa , Estresse Oxidativo , Estresse Fisiológico , Antioxidantes/metabolismo , Biocombustíveis
3.
J Chem Phys ; 134(23): 234304, 2011 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-21702553

RESUMO

The molar spin susceptibilities χ(T) of Na-tetracyanoquinodimethane (TCNQ), K-TCNQ, and Rb-TCNQ(II) are fit quantitatively to 450 K in terms of half-filled bands of three one-dimensional Hubbard models with extended interactions using exact results for finite systems. All three models have bond order wave (BOW) and charge density wave (CDW) phases with boundary V = V(c)(U) for nearest-neighbor interaction V and on-site repulsion U. At high T, all three salts have regular stacks of TCNQ(-) anion radicals. The χ(T) fits place Na and K in the CDW phase and Rb(II) in the BOW phase with V ≈ V(c). The Na and K salts have dimerized stacks at T < T(d) while Rb(II) has regular stacks at 100 K. The χ(T) analysis extends to dimerized stacks and to dimerization fluctuations in Rb(II). The three models yield consistent values of U, V, and transfer integrals t for closely related TCNQ(-) stacks. Model parameters based on χ(T) are smaller than those from optical data that in turn are considerably reduced by electronic polarization from quantum chemical calculation of U, V, and t of adjacent TCNQ(-) ions. The χ(T) analysis shows that fully relaxed states have reduced model parameters compared to optical or vibration spectra of dimerized or regular TCNQ(-) stacks.


Assuntos
Magnetismo , Metais Alcalinos/química , Nitrilas/química , Teoria Quântica , Sais/química
4.
Langmuir ; 26(22): 17546-51, 2010 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-20961061

RESUMO

Ferro- and ferrimagnetic nanoparticles are difficult to manipulate in solution as a consequence of the formation of magnetically induced nanoparticle aggregates, which hamper the utility of these particles for applications ranging from data storage to bionanotechnology. Nonmagnetic shells that encapsulate these magnetic particles can reduce the interparticle magnetic interactions and improve the dispersibility of the nanoparticles in solution. A route to create uniform silica shells around individual cobalt ferrite nanoparticles--which uses poly(acrylic acid) to bind to the nanoparticle surface and inhibit nanoparticle aggregation prior to the addition of a silica precursor--was developed. In the absence of the poly(acrylic acid) the cobalt ferrite nanoparticles irreversibly aggregated during the silica shell formation. The thickness of the silica shell around the core-shell nanoparticles could be controlled in order to tune the interparticle magnetic coupling as well as inhibit magnetically induced nanoparticle aggregation. These ferrimagnetic core-silica shell structures form stable dispersion in polar solvents such as EtOH and water, which is critical for enabling technologies that require the assembly or derivatization of ferrimagnetic particles in solution.


Assuntos
Cobalto/química , Compostos Férricos/química , Magnetismo , Nanoestruturas/química , Dióxido de Silício/química , Microscopia Eletrônica de Transmissão , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria
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