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In this paper, the suppression effect of baffle on VIV of cylinder at different depths is studied. According to two-dimensional transient model and RANS equation, VIV responses of a cylinder with two baffle plates at a fixed distance and a fixed Angle at different depths are numerically simulated. The submersion depth radio h * is mainly 1.2, 1.5, 2.5 and 5. The experimental data and predicting results are compared to display the accuracy of numerical method. When h * is 2.5, the baffle plates have the best suppression effect on VIV. Compared to the bare cylinder, the amplitude is decreased by 69%. Meanwhile, the vibration of the cylinder at different depths shows instability, and the motion response has great jitter. The lower baffle plate is subject to a unidirectional force when h * = 1.5 and 1.2. • The vibration of the cylinder under four submerged depths is studied. • Near the free surface, the baffle plates can suppress the vibration of the cylinder. • There is an interaction between the baffle and the free surface. • The vortex shedding of the baffle and cylinder will fuse and affect the free surface. • The best suppression effect of the baffle plates on the cylinder vibration is 69%. [ABSTRACT FROM AUTHOR]

Floating marine debris (FMD) is a pervasive problem in marginal seas worldwide. Driven by the nearshore waves, the FMD gradually accumulates shoreward and has a large chance of being beached, posing a direct threat to the coastal environment. Thus, investigating the nearshore drifting and beaching process of the FMD is of paramount importance. In this article, the trajectories of the FMD on a sloping beach are simulated by the Smoothed Particle Hydrodynamics (SPH) method, which is pre-verified through laboratory experiments. A series of sensitivity tests are conducted numerically on the influence of attributes of FMD as well as varied wave height (H 0), and wave period (T 0) on its beaching process. It is found that the beaching process of the FMD can be divided into three steps: drifting in front of surf zones, surfing and leaping with plunging waves, and advancing via wave runup. The density of the FMD combined with wave steepness determines whether the FMD can enter into the surf zone where it has a large chance to beach. Finally, this article proposed a semi-analytical model with improved Morison's equations considering the second-order Lagrangian transport on a sloping beach. This semi-analytical model is much faster and is comparable in computational accuracy to the high-resolution SPH model. It has the potential to be incorporated into the existing marine models and replace the stochastic process assumed for the FMD's tracking in the nearshore, in order to achieve more accurate assessment on the stranded FMD. [Display omitted] • Beaching process of floating marine debris is simulated by SPH method. • Beaching process is divided into three steps: drift, surf and leap, and translation. • Debris properties and offshore wave conditions codetermine whether debris beach. • Morison's equation is improved to predict debris trajectory before wave breaks. [ABSTRACT FROM AUTHOR]

A recently developed high Mn austenitic steel damper was found to show an excellent low-cycle fatigue resistance, irrespective of specimen size. To explain the robustness against specimen size, this study proposes a probabilistic prediction method for the effect of specimen size on fatigue life. In the present study, a Fe-30Mn-4Si-2Al model austenitic alloy that shows a superior low-cycle fatigue property was used as a case study. The prediction method is based on the measurement results of the rate of fatigue subcrack propagations, which are separated into two parts: small and large fatigue crack propagations. An important aspect of the prediction is the scatter characteristics of the small and large fatigue crack propagations; the former showed a large scatter in the propagation rate data, while the latter did not show large scatter data. Based on the scatter, two characteristic crack lengths were introduced in the probabilistic analyses: a) a boundary, l 0 , for small and large fatigue crack propagations, and b) a critical fatigue crack length for fracture, l f . Moreover, the effect of specimen size on the small fatigue crack propagation scatter was estimated using a Poisson distribution. The effect of specimen size on the large fatigue crack propagation part was estimated by an exponential approximation of the relationship between fatigue crack length and number of cycles after the l 0 . In addition, the boundary condition between the fatigue crack propagation and the fracture was determined using the critical fatigue crack length for fracture obtained from a fractograph. According to our prediction model, the small fatigue crack propagation lives decreased with an increase in the specimen size, and the large crack propagation lives increased with an increase in the specimen size. [ABSTRACT FROM AUTHOR]

Diphenylamine derivatives have been reported with good fungicidal, insecticidal, acaricidal, rodenticidal and/or herbicidal activities. To find new lead compound of this kind, a series of novel diphenylamine derivatives were designed and synthesized by the approach of Intermediate Derivatization Methods. All compounds were identified by 1 H NMR and elemental analysis. Bioassays demonstrated that some compounds substituted at 2,4,6-positions or 2,4,5-positions of phenyl ring B exhibited excellent fungicidal activities. The optimal compounds P30 and P33 showed 80% and 85% control respectively against cucumber downy mildew at 12.5 mg L −1 , both 100% control against rice blast at 0.3 mg L −1 and both 100% control against cucumber gray mold at 0.9 mg L −1 . The relationship between structure and fungicidal activities was discussed as well. [ABSTRACT FROM AUTHOR]

A deterministic Extreme Value Analysis method is of particular importance in an engineering-oriented context. In this paper, three extreme value analysis (EVA) methods, in which annual maxima, monthly maxima or the Peaks-Over-Threshold are fitted into Generalized Extreme Value distribution (GEV) function or Generalized Pareto distribution (GP) function, are used to estimate return values of significant wave height. Sensitivity of return levels on water depth and sampling length is vigorously investigated, based on a 40-year long and high-resolution wave hindcast for the South Yellow Sea (SYS). A spatially-and-temporally varied POT sampling method combined with GP function produces most conservative and confident estimates of return levels for a large return period, but produces wider confidence level than the other two EVA approaches based on GEV function for short return period. In the SYS, the return level estimates are significantly reduced with a longer sample length. However, we find that the reduction is closely related to the long-term trend in extreme wave heights, rather than due to the sampling effect. From deep to shallow waters, spatial inhomogeneity of return levels increases, which should be considered in the engineering practice. • A sophisticated investigation was conducted on the dependence of the return level of extreme wave heights in the SYS to the epistemic and intrinsic factors. • GEV distribution model is more confident in short-term return level estimates, whilst GP distribution model is more confident for long-term return level estimates. • The inter-tidal region although is least sensitive to sampling length for the return level estunates, whilst contains the largest spatial inhomogeneity of extreme wave heights. • A temporal negative long-term trend was found in the return levels of extreme wave height in the SYS. [ABSTRACT FROM AUTHOR]

Highlights: [•] Application of the strategies of intermediate derivatization method. [•] Trifluoromethyl, a very strong electron withdrawing group, plays an important role on fungicidal activity. [•] Characterization of target compounds using 1H NMR, 13C NMR, 19F NMR, elemental analysis, HRMS and X-ray. [•] Excellent fungicidal activity against Puccinia polysora. [•] Detailed structure and activity relationship of target compounds. [Copyright &y& Elsevier]

Abstract: A series of new strobilurin–pyrimidine analogs were designed and synthesized based on the structures of our previously discovered antiproliferative compounds I and II. Biological evaluation with two human cancer cell lines (A549 and HL60) showed that most of these compounds possessed moderate to potent antiproliferative activity. Two potent candidates (8f, IC50 =2.2nM and 11d, IC50 =3.4nM) were identified with nanomolar activity against leukemia cancer cell line HL60 for further development. This activity represents a 1000- to 2500-fold improvement compared to the parent compounds I and II and is 20- to 30-fold better than the chemotherapy drug, doxorubicin. The present work provides strong incentive for further development of these strobilurin–pyrimidine analogs as potential antitumor agents for the treatment of leukemia. [Copyright &y& Elsevier]

Abstract: A series of mesostructured H3PW12O40–titania materials with two-dimensional hexagonal, three-dimensional cubic, and three-dimensional interconnected sponge-like pore geometries were developed by using a single step nonionic-surfactant-templating strategy combined with evaporation-induced self-assembly (EISA) or hydrothermal treatment technique. The mesostructure, morphology, porosity, optical absorption property as well as composition and structure of as-prepared materials were well-characterized. Subsequently, the materials were successfully applied to the degradation of an aqueous diethyl phthalate (a kind of endocrine disrupting chemical) under the simulated sunlight irradiation at λ >320nm and λ >400nm region, respectively, and special attention was paid to investigate the influences of the structural orderings, pore geometries, H3PW12O40 loadings as well as calcination temperature on the photocatalytic performance of the H3PW12O40–titania materials to the target reaction. [ABSTRACT FROM AUTHOR]

Abstract: A series of ordered mesoporous H3PW12O40/TiO2 composite materials with different H3PW12O40 loadings were prepared by an evaporation-induced self-assembly (EISA) route in the presence of a triblock copolymer surfactant. The materials exhibited 2D hexagonal p6mm symmetry and anatase phase structure with large BET surface area and uniform pore size as well as narrowed bandgap with respect to neat TiO2. The photocatalytic activity of the H3PW12O40/TiO2 materials was evaluated by the degradation of an aqueous dye methyl orange under solar simulating Xe lamp irradiation, and enhanced photocatalytic activity compared to pure TiO2 was obtained for the samples with suitable H3PW12O40 loadings. [Copyright &y& Elsevier]

We aimed to establish a representative exposure response function between PM 2.5 and lung cancer to evaluate the impact on lung cancer burden and the benefits gained in association with the environmental policy change in Beijing, China. Based on population-based cancer registration data during 2001–2016, using a spatiotemporal Poisson regression model, long-term concentrations of PM 2.5 were linked to sex-age adjusted incidence rates of total lung cancer and its pathological subtypes. We calculated the health and monetary benefits associated with air quality improvement using the cost of illness method. In the constructed regression model, a 10 μg/m3 increment of PM 2.5 was associated with increases of 6.0% (95% confidence interval [95% CI]: 4.3%, 7.7%), 14.8% (10.3%, 19.4%), and 6.5% (3.3%, 9.8%) in the incidence of total lung cancer, squamous cell carcinoma, and adenocarcinoma, respectively. The estimated associations indicate that long-term exposure to PM 2.5 contributed 1947 to 3059 incident cases of lung cancer per year among the residents in Beijing during the study period. Clean air actions saved 4978 (95% CI: 2711, 7417) lung cancer cases, which brought a savings of 218 (118, 324) million RMB (~31 [17, 46] million US dollars) in direct inpatient medical expenditures. If air quality had met national standards of long-term PM 2.5 (35 μg/m3) in 2014–2016, 10,003 (95% CI: 9325, 10,650) lung cancer cases could have been prevented and direct inpatient medical expenditures of 438 (409, 466) million RMB (~63 [58, 67] million US dollars) could have been saved. This study enriches epidemiological study, confirming the association between exposure to PM 2.5 and lung cancer or its subtypes, and provides novel evidence for the notable reduction in lung cancer burden and medical expenditure savings that were achieved through air quality improvements in Beijing from 2014 to 2016. Unlabelled Image • An ambient PM 2.5 exposure-lung cancer risk function was developed. • PM 2.5 exposure was associated with increased risk of lung cancer. • The effect was stronger for squamous cell carcinoma than adenocarcinoma. • Lung cancer risk attributable to PM 2.5 decreased during 2001 through 2016. • The clean air actions saved substantial medical costs by preventing lung cancer. [ABSTRACT FROM AUTHOR]