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The adakitic dikes with zircon ages of ~120–118 Ma are identified in the Xiejiagou gold deposit, Jiaobei terrain. The Early Cretaceous intermediate-acidic dikes include monzonite, quartz monzonite, and monzogranite, which have SiO2, Al2O3, K2O, Na2O contents ranging from 61.01 to 74.72 wt. %, 14.42 to 17.28 wt.%, 2.55 to 4.45 wt.%, and 3.09 to 4.64 wt.%, respectively. The dikes are enriched in large ion lithophile elements (LILEs) (e.g., Rb, Sr, and Ba) and light rare earth elements (LREEs), but are depleted in high field strength elements (HFSEs) (e.g., Nb, Ta) and heavy rare earth elements (HREEs). They are also characterized by continental crust-like isotopic compositions: whole-rock δ18O = 7.6–9.9‰, (87Sr/86Sr)i = 0.70893–0.71036, and εNd(t) = −13.16 to −17.06. Assimilation and fractional crystallization are limited, and partial melting of source rock is the main mechanism in controlling the compositional variation. The high Sr/Y (41.51–93.25) and (La/Yb)N (22.9–44.7) ratios imply that the dikes have affinities similar to adakitic rocks. The regional geological setting, coupled with the geochemical and isotopic data, indicate that the adakitic dikes were unlikely produced by partial melting of a subducted oceanic slab or a thickened/delaminated lower crust, or AFC processes of mantle-derived magmas. We conclude that the adakitic dikes are generated by partial melting of lower crust which was triggered and modified by underplating of the lithospheric mantle. We also propose that the eastern part of the North China Craton experienced severe thinning in the Early Cretaceous (~135–120 Ma), and the lithospheric thinning is related to delamination of the lower crust. [ABSTRACT FROM AUTHOR]

Marine plankton are faced with novel challenges associated with environmental changes such as ocean acidification, warming, and eutrophication. However, data on the effects of simultaneous environmental changes on complex natural communities in coastal ecosystems are relatively limited. Here we made a systematic analysis of biological and environmental parameters in the Bohai Sea over the past three years to suggest that plankton communities responded differently to current changing coastal environments, with the increase of phytoplankton and the decrease of zooplankton. These different changes of phyto- and zooplankton potentially resulted from the fact that both the effect of acidification as a result of pH decline and the effect of warming as a consequence of increasing temperature favored phytoplankton over zooplankton at present. Furthermore, water eutrophication and salinity as well as heavy metals Hg, Zn, and As had more or less diverse consequences for the dynamics of phytoplankton and zooplankton. Differently, with ongoing climate change, we also revealed that both phytoplankton and zooplankton would decrease in the future under the influence of interactions between acidification and warming. • Plankton responded differently to current changing coastal environments. • Current coastal environments benefit phytoplankton but harm zooplankton. • Plankton would decrease under future acidification and warming. [ABSTRACT FROM AUTHOR]

Mittag–Leffler stability is a property of fractional‐order dynamical systems, also called fractional Lyapunov stability, requiring the evolution of the positive‐definite functions to be Mittag–Leffler, rather than the exponential meaning in Lyapunov stability theory. Similarly, fractional Lyapunov function plays an important role in the study of Mittag–Leffler stability. The aim of this study is to create closed‐loop systems for commensurate fractional‐order non‐linear systems (FONSs) with Mittag–Leffler stability. We extend the classical backstepping to fractional‐order backstepping for stabilising (uncertain) FONSs. For this purpose, several conditions of control fractional Lyapunov functions for FONSs are investigated in terms of Mittag–Leffler stability. Within this framework, (uncertain) FONSs Mittag–Leffler stabilisation is solved via fractional‐order backstepping and the global convergence of closed‐loop systems is guaranteed. Finally, the efficiency and applicability of the proposed fractional‐order backstepping are demonstrated in several examples. [ABSTRACT FROM AUTHOR]

Abstract: Simple central force optimization (SCFO) algorithm is a novel physically-inspired optimization algorithm as simulating annealing (SA). To enhance the global search ability of SCFO and accelerate its convergence, a novel extended/enhanced central force optimization (ECFO) algorithm is proposed through both adding the historical information and defining an adaptive mass. SCFO and ECFO are all motivated by gravitational kinematics, in which the compound gravitation impels particles to the optima. The convergence of ECFO is proved based on a more complex characteristic equation than SCFO, i.e. the second order difference equation. The stability theory of discrete-time-linear system is used to analyze the motion equations of particles. Stability conditions limit their eigenvalues inside the unit cycle in complex plane and corresponding convergence conditions are deduced related with ECFO’s parameters. Finally, ECFO are tested against a suite of benchmark functions with deterministic and excellent results. Experiments results show that ECFO converges faster than SCFO with higher global searching ability. [Copyright &y& Elsevier]

Rydberg atoms-based electric field sensing has developed rapidly over the past decade. A variety of theoretical proposals and experiment configurations are suggested and realized to improve the measurement metrics, such as intensity sensitivity, bandwidth, phase, and accuracy. The Stark effect and electromagnetically induced transparency (EIT) or electromagnetically induced absorption (EIA) are fundamental physics principles behind the stage. Furthermore, various techniques such as amplitude- or frequency-modulation, optical homodyne read-out, microwave superheterodyne and frequency conversion based on multi-wave mixing in atoms are utilized to push the metrics into higher levels. In this review, different technologies and the corresponding metrics they had achieved were presented, hoping to inspire more possibilities in the improvement of metrics of Rydberg atom-based electric field sensing and broadness of application scenarios. [ABSTRACT FROM AUTHOR]

Dissolved organic matter (DOM) is ubiquitous and widespread in natural water and influences the transformation and removal of antibiotics. Nevertheless, the influence of DOM molecular weight (MW) on the indirect photodegradation of antibiotics has rarely been reported. This study attempted to explore the influence of the molecular weight of DOM on the indirect photodegradation of two fluoroquinolone antibiotics (FQs), ofloxacin (OFL) and norfloxacin (NOR), by using UV–vis absorption and fluorescence spectroscopy. The results showed that indirect photodegradation was considered the main photodegradation pathway of FQs in DOM fractions. Triplet-state excited organic matter (3DOM*) and singlet oxygen (1O 2) were the main reactive intermediates (RIs) that affected the indirect photodegradation of FQs. The indirect photodegradation rate of FQs was significantly promoted in DOM fractions, especially in the low molecular weight DOM fractions (L-MW DOM, MW < 10 kDa). The results of excitation-emission matrix spectroscopy combined with parallel factor analysis (EEM-PARAFAC) showed that terrestrial humic-like substances had a higher humification degree and fluorophore content in L- MW DOM fractions, which could produce more 3DOM* and 1O 2 to promote the indirect photodegradation of FQs. This study provided new insight into the effects of DOM at the molecular weight level on the indirect photodegradation of antibiotics in natural water. [Display omitted] • The highest indirect photolysis rate was found in low molecular weight fractions. • 3DOM* and 1O 2 made more contribution to the FQs indirect photodegradation. • Terrestrial humic-like components contributed more to FQs indirect photolysis. • Low molecular weight DOM contained more terrestrial humic-like substances. [ABSTRACT FROM AUTHOR]

The equal percent removal (EPR) method, in which pollutant reduction ratio was set as the same in all administrative regions, failed to satisfy the requirement for water quality improvement in the Bohai Sea. Such requirement was imposed by the developed Coastal Pollution Total Load Control Management. The total maximum allocated load (TMAL) of nitrogen pollutants in the sea–sink source regions (SSRs) around the Bohai Rim, which is the maximum pollutant load of every outlet under the limitation of water quality criteria, was estimated by optimization–simulation method (OSM) combined with loop approximation calculation. In OSM, water quality is simulated using a water quality model and pollutant load is calculated with a programming model. The effect of changes in pollutant loads on TMAL was discussed. Results showed that the TMAL of nitrogen pollutants in 34 SSRs was 1.49×10 5 ton/year. The highest TMAL was observed in summer, whereas the lowest in winter. TMAL was also higher in the Bohai Strait and central Bohai Sea and lower in the inner area of the Liaodong Bay, Bohai Bay and Laizhou Bay. In loop approximation calculation, the TMAL obtained was considered satisfactory for water quality criteria as fluctuation of concentration response matrix with pollutant loads was eliminated. Results of numerical experiment further showed that water quality improved faster and were more evident under TMAL input than that when using the EPR method [ABSTRACT FROM AUTHOR]

Abstract Simulation–optimization approaches are widely used in land-based pollutant load allocation and management. However, existing simulation–optimization approaches do not optimize the entire pathway of pollution (i.e., generation, transportation, and emission). Thus, the selected allocated load scheme and its reduction management are incomplete and non-optimal in supporting effective reduction measures to set in further. This study aims to establish a simulation–optimization load allocation approach covering the entire pathway of pollution and construct separate allocated loads for each migration process. By comparing the allocated loads to the actual pollutant loads, the critical and developable pollution source regions (CPSRs and DPSRs) and the critical pollution migration processes (CPMPs) are identified, and specific pollution management indicators are established for each pollution source region. This approach is applied to the Bohai Rim, which is currently a major economic development center with a most seriously deteriorating sea area in China. The CPSRs, DPSRs, and CPMPs for total nitrogen are identified, and comparisons of the management indicators with existing approaches are made. Water quality under the allocated load emissions is simulated via a simulation water quality model and compared with that of the actual pollutant loads. Quantitative results indicate that the new approach combines the specific mitigation indicators for each CPSR and CPMP when allowing the extra generation of allocated loads for DPRSs while keeping the water quality of the Bohai Sea under control. Graphical abstract Unlabelled Image Highlights • Pollutant loads are allocated among the entire migration pathway. • Reductions and development capacity are considered. • Critical and developable source regions and migration processes are identified. • Specific management indicators for each source region and migration process are established. [ABSTRACT FROM AUTHOR]

three-dimensional advection-diffusion model coupled with the degradation process is established for describing the transport of chemical oxygen demand (COD). Comparison of the simulated distribution of COD at the surface in the Bohai Sea in August, 2001 with field observations, shows that the model simulates the dataset reasonably well. The Laizhou Bay, Bohai Bay, and Liaodong Bay were contaminated heavily near shore. Based on the optimal discharge flux method, the Environmental Capacity (EC) and allocated capacities of COD in the Bohai Sea are calculated. For seawater of Grades I to IV of the Chinese National Standard, the ECs of COD in the Bohai Sea were 77×10 t/a, 116×10 t/a, 154×10 t/a and 193×10 t/a, respectively. The Huanghe (Yellow) River pollutant discharge accounted for the largest percentage of COD at 14.3%, followed by that of from the Liugu River (11.5%), and other nine local rivers below 10%. The COD level in 2005 was worse than that of Grade II seawater and was beyond the environmental capacity. In average, 35% COD reduction is called to meet the standard of Grade I seawater. [ABSTRACT FROM AUTHOR]