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Feed-in tariffs (FITs) are among the most favoured policies with which to drive the deployment of renewable energy. This paper offers insights into quantifying dynamic FITs to realise the expected installed capacity target with minimum policy cost under uncertainties of renewable intermittence and technology learning. We incorporate real options and use stochastic dynamic programming to model the strategic behaviour between policy-maker and investor and extend the one-time investment decision described by Farrell et al. [2017. 'Specifying an Efficient Renewable Energy Feed-in Tariff.' The Energy Journal 38: 53–75] to multiple-period decisions. An approach that combines binary tree scenario generation and a least squares Monte Carlo method is used to numerically identify the optimal FITs plan in practice. China's offshore wind power investment is used as a case study to investigate the relationships among the optimal dynamic FITs level, the total policy cost, the expected capacity target, and the learning effect. The simulation results demonstrate that our proposed dynamic FITs can track the changes in technology learning well and that they can avoid the inefficiency of fixed FITs in stimulating technology adoption in the initial periods, along with overpayment by the policy-maker. [ABSTRACT FROM AUTHOR]

The application of series dual burning rate grain can improve specific impulse of nozzleless solid rocket motor (NSRM). In this paper, burning-rate ratio is the ratio of main propellant burning rate and nozzle propellant burning rate in dual burning rate grain, which has significant influence on NSRM performance. Focusing on relationship between burning-rate ratio and motor performance, internal ballistics simulation of NSRM with different burning-rate ratios has been carried out. Results show that, with the increase of burning-rate ratio, total impulse grows monotonically, while maximum head pressure has two variation stages – the stable stage and the increasing stage. By analyzing the head pressure curves, it is known that maximum head pressure is almost equal to the higher one of initial stage head pressure (p1) and combustion ending stage head pressure (p2). Relationship between p2/p1 and burning-rate ratio has been established by linear fitting, and the critical burning-rate ratio, which is the maximum burning-rate ratio to ensure that maximum head pressure almost is kept invariant, has been obtained. Critical burning-rate ratio has no significant change when geometry size remains invariant. Utilizing critical burning-rate ratio in NSRM with series dual burning rate grain, specific impulse can be enhanced with nearly no sacrifice of maximum head pressure performance. These results can provide references for NSRM designing and optimizing. [ABSTRACT FROM AUTHOR]

In this article, based on the existing literature, we extend a deterministic delayed SIS epidemic model with vaccination to the stochastic version. First, we show that the solution of system is globally unique, positive and stochastically bounded. Then, constructing suitable Lyapunov function, we study the stochastic stability of system at the disease-free equilibrium. Moreover, the threshold R ̂ 0 which determines the extinction or persistence in time mean of the disease is proposed. When R ̂ 0 is less than 1, the disease will disappear; while R ̂ 0 is greater than 1, the disease will persist. Moreover, we study the existence of the ergodicity and the stationary distribution of the model, which can help us better understand the dynamic behavior and statistical characteristics of stochastic delayed biological models. Finally, we apply the results to hepatitis B in Chinese mainland. Using the nonlinear Least-Square method, we estimate the parameter of the model and obtain the threshold R ̂ 0 = 0.0556. We forecast that hepatitis B infections in Chinese mainland will drop to about 20 million in 2100 from 90 million in 2015, and give the probability densities of Hepatitis B infections each year. [ABSTRACT FROM AUTHOR]

While ex-ante evaluations of climate mitigation policies predict that co-benefits of improved air quality will enable the aggregate benefits of climate mitigation policies to outweigh their costs, there is little empirical evidence to support this assertion. In this study, we use data on weekly smokestack emissions of sulfur dioxide (SO2) from firms participating in Shanghai's carbon dioxide (CO2) emissions trading scheme (ETS) to deliver one of the first ex-post evaluations on the co-benefits of China's ETS. Using a panel-regression model in which all firms' characteristics and seasonal effects are controlled, we find a significant negative association between CO2 emissions prices and industrial SO2 emissions (elasticity of −0.13). A closer examination reveals that most of these effects were driven by specific sectors (iron and steel) and during months in which firms were required to balance their annual CO2 emissions. To ensure our results are not driven by confounding factors and our model's assumptions, we conducted several falsification checks using SO2 emissions from non-ETS firms and firms from a nearby city, using various model specifications. Our findings suggest that co-benefits from climate mitigation policies should not be taken for granted, and that policy designs and types of sector sources of emissions are important determinants of co-benefits. Key policy insights The study provides empirical evidence for air pollution co-benefits of a CO2 ETS using weekly smokestack-level data from Shanghai, China Evidence from the Shanghai ETS shows that a 1% increase in CO2 prices in Shanghai is associated with a 0.13% decrease in SO2 emissions These co-benefits, however, are limited to specific sectors (e.g. ferrous metals), and are not found in other major CO2 emitting sources or sectors (e.g. power utilities) The relationship between CO2 prices and co-benefits is also stronger during months in which firms are required to balance their annual CO2 emissions using permits [ABSTRACT FROM AUTHOR]

In this study, advanced treatment of heavily polluted oilfield production wastewater (OPW) was investigated employing the combination of coagulation/dissolved air flotation, heterogeneous catalytic ozonation and sequencing batch reactor (SBR) processes. Two SBR reactors were separately set up before and after the ozonation unit. The results show that microbubble flotation was more efficient than macrobubble flotation in pollutant removal. Catalytic ozonation with the prepared Fe/activated carbon catalyst significantly enhanced pollutant removal in the second SBR by improving wastewater biodegradability and reducing wastewater microtoxicity. The treatment technique decreased oil, chemical oxygen demand and NH3-N by about 97%, 88% and 91%, respectively, allowing the discharge limits to be met. Therefore, the integrated process with efficient, economical and sustainable advantages was suitable for advanced treatment of real OPW. [ABSTRACT FROM PUBLISHER]

A ratiometric fluorescent zinc probe 1 of carboxamidoquinoline with a carboxylic acid group was designed and synthesised. Probe 1 exhibits high selectivity for sensing Zn2+; about a 13-fold increase in fluorescence emission intensity and an 82 nm red-shift of fluorescence emission are observed upon binding Zn2+ in EtOH/H2O (1 : 1, V/V) solution. The ratiometric fluorescence response is attributed to the 1 : 1 complex formation between probe 1 and Zn2+ which has been utilised as the basis for the selective detection of Zn2+. The analytical performance characteristics of the proposed Zn2+-sensitive probe were investigated. The linear response range covers a concentration range of Zn2+ from 2.0 × 10-6 to 5.0 × 10-5 mol L-1 and the detection limit is 2.7 × 10-7 mol L-1. The determination of Zn2+ in both tap and river water samples shows satisfactory results. [ABSTRACT FROM AUTHOR]

Quinoline-appended rhodamine B thiohydrazide based fluorescent probe was designed and applied in fluorescent detections of mercury ions in both aqueous solution and living cells. The signal change of the probe is based on a specific metal ion induced reversible ring-opening mechanism of a rhodamine B thiohydrazide. The probe exhibits a dynamic response concentration range for Hg2+ from 1.0 × 10-8 to 1.0 × 10-5 M with a detection limit of 8.5 × 10-9 M. The fluorescent probe is pH independent in medium condition and exhibits high selectivity over other common metal ions. [ABSTRACT FROM AUTHOR]

The methylation status of the androgen receptor gene (AR) in leukemia cell lines was investigated. Results showed the presence of both methylated and unmethylated CpG islands of the AR promotor in leukemia cell lines. In the normal blood samples, only unmethylated bands were observed. In 15 bone marrow samples from patients with leukemia, 12 cases (80%) showed both methylated and unmethylated alleles and 3 cases (20%) showed only methylated alleles. To understand whether AR mRNA and protein expression are reduced by methylation, we treated leukemia cells with 5-Aza-Dc and detected the expression of mRNA and protein by RT-PCR and immunohistochemistry. The treatment of 5-Aza-Dc increased AR expression in all cell lines researched. This study indicates that reduced AR mRNA expression in leukemia cell lines was in part related to DNA methylation. The aberrant methylation of AR gene could be one molecular and genetic alteration in leukemia. [ABSTRACT FROM AUTHOR]

The synthesis of a new compound, amide-linked diporphyrin xanthene(ADPX), and its application for preparation of lead(II) ion selective electrodes are described. The electrode was prepared with a PVC membrane combining ADPX as a neutral carrier, 2-nitrophenyl octyl ether (o-NPOE) as a plasticizer and sodium tetraphenylborate (NaTPB) as an additive in the percentage ratio of 3:3:65:32 (ADPX: NaTPB: o-NPOE: PVC, w:w). The electrode exhibited linear response with a near Nernstian slope of 28.2 mV per decade within the concentration range of 2.6×10-6 to 1.0×10-1 M lead ions, with a working pH range from 4.5 to 7.5, and a fast response time of less than 30 s. Selectivity coefficients for Pb(II) relative to a number of interfering ions were investigated. The electrode is highly selective for Pb2+ ions over a large number of cations. Several electroactive materials and solvent mediators have been compared and the experimental conditions were optimized. The sensor was applied as indicator electrode in titration of Pb(II) with potassium chromate solution with satisfied results. [ABSTRACT FROM AUTHOR]

The synthesis of a dimer of porphyrin linked by flexible alkoxyl chains and its application as neutral ionophore for a berberine-sensitive potentiometric sensor were described. The porphyrin dimer based sensor shows a linear response towards berberine in the range 1.2 × 10[SUP-7] -5.0 × 10[SUP-3] mol L[SUP-1], with a pH range from 3.7 to 11.2, a fast response time of 10s and a slope of 65.5 ± 2.5mV/dec. The proposed electrode exhibits different selectivity behavior compared with the electrode based on classical cation exchanger. As an electroactive material, porphyrin dimer shows better potentiometric response characteristics comparing to porphyrin monomer or metalloporphyrin. The effects of solvent mediator have been studied and the experimental conditions optimized. The interaction between BE[SUP+] and porphyrin dimer was investigated using UV-VIS spectrophotometry. The electrode can be used in the direct assay of BE in pharmaceutical preparations with satisfactory results. [ABSTRACT FROM AUTHOR]