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Elemental geochemical and Sr–Nd isotopic signatures are used to decipher terrigenous sediments provenances and transport mechanisms in the South Yellow Sea during the Holocene. 87 Sr/ 86 Sr ratios in the Chinese and Korean riverine sediments overlap each other, whereas εNd values of Korean riverine sediments are generally less radiogenic in comparison to the Changjiang and Huanghe. Moreover, εNd values of these two large rivers appear unaffected by mineral sorting and are relative stable during the Holocene. We propose a three endmembers (i.e., the Changjiang, the Huanghe, and Korean rivers) mixing model to explain sediment provenances in the Central Yellow Sea Mud (CYSM). Mixing calculations show that the Huanghe is the major sediment contributor to the CYSM before ~ 8 ka (thousand years before 1950 CE), whereas the Changjiang has become the predominant sediment source after ~ 8 ka. Holocene changes in riverine sediment supplies to the CYSM are closely related to the oceanic circulation, monsoon climate, and drainage changes. After examining several hypotheses to explain the variations in 87 Sr/ 86 Sr ratios of Core YSC-1 during the past ~ 8 kyr, we tentatively attribute that to changes in the erosion patterns of the Changjiang Basin. This in turn is associated with the asynchronous evolution of monsoon precipitation in the upper (Indian Summer Monsoon) and middle-lower Changjiang (East Asian Summer Monsoon). Therefore, our results highlight significant influences of monsoon climate on erosion patterns within the Changjiang catchment at millennial timescales. [ABSTRACT FROM AUTHOR]

There are rich geothermal resources in China and they are widely distributed. After years of continuous exploration and production, most of the shallow geothermal resources have been explored and the current exploration mainly focuses on deep ones. Among a great many geophysical exploration methods, seismic survey is the most effective means of geothermal resource exploration and production, but its weak seismic reflection signal, low S/N ratio and poor imaging of thermal reservoirs due to the seismic geological conditions restrict the production and utilization of deep geothermal resources. It considers through the analysis of the geophysical characteristics of the thermal reservoir that the main causes for the weak seismic reflection signals from deep thermal reservoirs are (1) the shielding effect of the strong wave impedance interface between the thermal reservoir and the caprocks; (2) the small reflection coefficient inside the thermal reservoir; and (3) the serious absorption and attenuation of high-temperature fluids such as hydrothermal fluids and steam in the thermal reservoirs by seismic waves. Accordingly, a series of seismic data acquisition technologies are proposed based on the high-precision vibroseis low-frequency shooting, high-sensitivity geophones long-spread receiving and small bin size highfold technologies, and their application in the seismic acquisition of dry-hot rocks (HDR) in Gonghe Basin, Qinghai, shows a very good application effect. [ABSTRACT FROM AUTHOR]

Factors influencing millennial-scale variability in the thermocline depth (vertical mixing) and sea surface salinity (SSS) of the southern Okinawa Trough (OT) during the past 17,300 years were investigated based on foraminifer oxygen isotope records of the surface dweller Globigerinoides ruber sensu stricto and the thermocline dweller Pulleniatina obliquiloculata in the AMS C dated OKT-3 core. The thermocline depth is influenced by surface thermal buoyancy (heat) flux, in turn controlled by the annual mean insolation at 30°N and the strength of the East Asian winter monsoon (EAWM). Strong insolation and weak EAWM tend to increase buoyancy gain (decrease buoyancy loss), corresponding to shallow thermocline depths, and vice versa. Regional SSS is influenced by the global ice volume, the Kuroshio Current (KC), and vertical mixing. A deep thermocline coincides with a high SSS because strong vertical mixing brings more, saltier subsurface KC water to the surface, and vice versa. Local SSS (excluding the global ice volume effect) became lower in the northern OT than in the southern OT after ~9.2 ka, implying that Changjiang diluted water had stronger influence in the northern sector. SSS show no major changes during the Bølling/Allerød and Younger Dryas events, probably because the KC disturbed the North Atlantic signals. This argues against earlier interpretations of sea surface temperature records of this core. Wavelet and spectral analyses of the ΔδO (δO of P. obliquiloculata minus G. ruber s.s.) and δO records display 1,540-, 1,480-, 1,050-, 860-, 640-, and 630-year periods. These are consistent with published evidence of a pervasive periodicity of 1,500 years in global climate as well as EAWM and KC signatures, and a fundamental solar periodicity of 1,000 years and intermediary derived periodicity of 700 years. [ABSTRACT FROM AUTHOR]

A standard AlGaN/AlN/GaN heterostructure field-effect transistor (HFET) on a 420 μm thick sapphire substrate was fabricated, and then the sapphire substrate was thinned to several different thicknesses by grinding. When the remaining substrate thickness is more than 170 μm, the characteristics of the substrate thinned AlGaN/AlN/GaN HFET are almost the same as the original device. However, when the substrate thickness is less than 170 μm, the drain-to-source current, the threshold voltage, and the electron mobility of the two-dimensional electron gas (2DEG) in the channel are varied compared to the original one. It is attributed to the shrinkage of the GaN layer with the reduction of substrate thickness, which induces the decrease of both the 2DEG sheet density and the polarization charge sheet density, and a possible increase of dislocation scattering and the reduction of polarization Coulomb field scattering. [ABSTRACT FROM AUTHOR]

Cu2O deposited on 2D continuous lamellar g-C3N4 (Cu2O/g-C3N4) was prepared via a facile impregnation–chemical reduction procedure. The composition, structure and morphology of as-prepared Cu2O/g-C3N4 were characterized by XRD, SEM, TEM, CO-TPR, FT-IR and nitrogen adsorption, respectively. The influence of Cu2O loading on the performances of Cu2O/g-C3N4, e.g. adsorption ability for methyl orange (MO) and the stability as well as catalytic activity for CO oxidation, was investigated. The changing trend of adsorption ability and the catalytic activity of Cu2O/g-C3N4 moved in the same direction. When the mass ratio of Cu2O to g-C3N4 was 4 : 10, the as-prepared composite exhibited the strongest adsorption ability and the highest catalytic activity; it also showed excellent stability in CO oxidation and over it the 100% conversion of CO was kept for more than 12 h under reaction conditions. The strong adsorption ability and good catalytic performance of Cu2O/g-C3N4 were ascribed to the synergetic effects between g-C3N4 and Cu2O as well as the improved dispersibility and the decreased particle size of Cu2O. [ABSTRACT FROM AUTHOR]

Abstract: The East China Sea (ECS) is characterized by a relatively high riverine martial input that is associated with East Asian monsoon systems. In this study, we investigated a 272cm-long sediment core (THB-2) from the ECS inner shelf for the AMS 14C dating, grain size, total organic carbon (TOC), total nitrogen (TN), and stable carbon and nitrogen (δ 13C and δ 15N) isotopes to provide insights into previous changes in the monsoon-climate and the intensity of the coastal upwelling. A three end-member (riverine, deltaic, and marine) mixing model was applied to determine the temporal variations in sedimentary organic matter sources. The transport and burial of the Changjiang riverine organic carbon in the ECS inner shelf is strongly controlled by the combined effects of the monsoon-climate and human activities during the late Holocene. The sedimentary δ 15N records of the THB-2 core are more complex and may be best explained by changes in the nutrient utilization in the coastal zone surface waters. The downcore variations of the marine organic matter-δ 15N are closely related to the intensity of East Asian summer monsoon during the last 3.6ka. The stronger East Asian summer monsoon likely favored the intensive coastal upwelling and additional Changjiang discharge during the 3.6–2.7ka and 0.4–0ka periods, which triggered the greater relative nitrate utilization in the coastal surface water. [Copyright &y& Elsevier]

• Adjusting distributed generations output based on marginal cost consistency. • Integrating pinning control and Q -learning algorithm via parameter passing. • Simulations demonstrate that adopting the reinforcement pinning algorithm can reduce operating costs of the microgrid and improve system stability. Traditional droop control allocates distributed generation (DG) power based on capacity proportion, which leads to high system operating costs. To address this issue, this study proposes a distributed economic control strategy for microgrids based on reinforcement pinning (RP) control. To minimize operating costs, reinforcement learning (RL) continuously updates the Q -value table through reward feedback to obtain the optimal strategy. The optimal action determined by RL is set as the pinning reference value and transmitted to the pinning agent. Other agents achieve marginal cost consistency through the pinning information iteration matrix. To correct frequency deviations, proportional-integral (PI) control is used to ensure frequency stability for the system's operation. Simulations under different scenarios were conducted in MATLAB/Simulink. The results show that the proposed approach can coordinate the output of distributed power sources, reduce the operating costs of the microgrid, and maintain frequency stability. [ABSTRACT FROM AUTHOR]

Hemostatic materials play a crucial role in trauma medicine. However, existing materials have poor hemostatic efficacy and a tendency to adhere to the wound surface, limiting their clinical effectiveness. Herein, a drug-loaded, superhydrophilic/superhydrophobic laminated material (DSLM), consisting of a superhydrophobic inner layer with a micropore array, a superhydrophilic chitosan-based sponge layer loaded with hemostatic/antimicrobial drugs, and a superhydrophobic outer layer, was developed. Furthermore, the DSLM allows unidirectional flow of blood and exudates from the wound bed through the superhydrophobic inner layer while facilitating efficient drug delivery. In addition, it possesses excellent biocompatibility and antiadhesion properties, as confirmed by in vivo and in vitro experiments. Compared with traditional hemostatic materials, the DSLM remarkably increased the survival time by over threefold in the acute femoral transaction wound bleeding model, and simultaneously prevented secondary wound damage by reducing peeling force to one-eighth incomparison to pristine gauze. The DSLM holds promise as a versatile clinical biomaterial for prehospital acute trauma treatment, with its simple structure facilitating manufacturing and expanding applications in biomedicine. • The DSLM enables unidirectional pumping and effective drug delivery. • DSLM's superhydrophobic gauze material is highly durable against mechanical damage and extreme conditions. • In vitro cell experiments confirm DSLM's biocompatibility, antibacterial traits, and ability to enhance blood coagulation. • DSLM outperforms traditional gauze in wound hemostasis, significantly prolonging rat survival time in tests. [ABSTRACT FROM AUTHOR]

[Display omitted] • The effect of hydration shells on uranium adsorption kinetics is deeply investigated. • The external diffusion can be facilitated due to fast water exchange. • The increasing temperature would reduce the apparent friction during mass transfer. • The adsorption equilibrium time can be shortened from 32 days down to 18 days. Identifying mass transfer is essential for boosting adsorption kinetics. The internal and external diffusions serve as rate-limiting steps. The liquid film diffusion is commonly identified as external diffusion, while the mass diffusion across the ubiquitous hydration shell is generally ignored. Charged functional groups can bind water molecules strongly via electrostatically induced hydration. Herein, three representative polar polymers, including cation polymer (PDMAPAA), anion polymer (PSS) and zwitterion polymer (PSBMA), are crosslinked with polyamioxime (PAO) to synthesize radially aligned PAO-PDMAPAA, PAO-PSS, PAO-PSBMA, respectively, by a bidirectional freeze-casting. We focus on the effect of hydration structure and hydration dynamics on marine uranium extraction performance. It is found that the external diffusion in PAO-polar polymer adsorbents can be facilitated due to fast water exchange in dynamic hydration shell, leading to a reduced adsorption equilibrium time compared with the pristine PAO. However, the high hydration degree causes strong viscous shear and high dehydration barrier, which impede the complexation of UO 2 2+ with binding sites of PAO. Although the hydration degree follows the order of PAO-PSBMA > PAO-PDMAPAA > PAO-PSS, PAO-PDMAPAA delivers the shortest equilibrium time required. In addition, the increasing temperature would weaken viscous shear in static hydration shell, which equivalently reduces the apparent friction of hydrated uranyl ions. Consequently, light-irradiated GO@PAO-PDMAPAA adsorbent, in which GO acts as a photothermal mediator, yields a shorter equilibrium time (∼18 days) than PAO-PDMAPAA together with a high uranium adsorption capacity of 12.24 mg-U/g-Ads in natural seawater. These findings provide valuable guidance for enhancing uranium adsorption kinetics associated with hydration shell. [ABSTRACT FROM AUTHOR]

Deep-sea sediments are ideal recorders for studying the provenances and relevant chemical and physical weathering of adjacent lands. Major, trace (Fe, K, Al, Ti, V, Rb, Th, and Cr), and rare earth elements (REEs), grain size, and AMS 14C ages were studied on a 4-m-long core CS11 collected from a deep basin in the northern South China Sea (SCS). Core CS11 sediments were mainly derived from southwestern Taiwan Island and transported by the southward bottom current during most of the study periods, except from 37 to 35 kyr BP, when northern Luzon inputs temporarily had influence. For the past 35 kyr, the stacked chemical weathering index (SCWI) correlated well with the worldwide Younger Dryas (YD), Heinrich 1 (H1), Heinrich 2 (H2), and Heinrich 3 (H3) events, indicating global climate control on weathering intensity in this area. However, the SCWI showed the strongest chemical weathering intensity during the low sea level at the Last Glacial Maximum (LGM) when Taiwan-derived sediments were subaerially exposed on the shelf, chemically weathered and increasingly transported to the deep basin of the SCS. The major factors influencing chemical weathering intensities for sediments in the deep basin of the northern SCS varied on different geological time scales, with climate changes on millennial scales and sea-level changes on orbital scales. • Sediments in the deep basin of the northern South China Sea (SCS) were derived mainly from southwestern Taiwan. • Rapid changes in weathering intensity were synchronized with cold/dry events on millennial scales. • The strongest weathering of sediments occurred during the Last Glacial Maximum. • Weathering intensity was dominated by provenance variation controlled by sea level changes on orbital scales. [ABSTRACT FROM AUTHOR]

The increasing integration of distributed energy resources has led to heightened complexity in distribution network models, posing challenges of uncertainty and volatility to the operation and control of distribution networks. Simultaneously, the widespread deployment of metering and sensing devices has furnished data-driven approaches with copious data sources. As a potent tool for data mining, artificial intelligence (AI) algorithms have the capacity to harness extensive datasets, thus furnishing comprehensive energy services for distribution grids. This paper provides a comprehensive exposition of AI techniques applied in the realm of distribution network voltage control (DNVC). Initially, a brief overview is provided for the four voltage control frameworks and the data calibration of DNVC, serving as the foundation for various voltage control algorithms. Subsequently, in ascending order of algorithmic advancement, the application of improved heuristic algorithms, deep learning (DL) algorithms structured around artificial neural networks (ANNs), and deep reinforcement learning (DRL) algorithms in the DNVC domain are sequentially introduced, and the relationships among the three AI technologies in framework, control principles, and performance are systematically analyzed. Additionally, attention is directed toward the algorithmic progress made in addressing specific challenges within the DNVC process. Lastly, building upon extant research, the paper summarizes four prominent developmental directions for AI in DNVC: safety exploration, information privacy, multi-feeder collaboration, and heightened uncertainty. Corresponding solutions to each of these directions are individually discussed. • The research status and applications of mainly used AI methods in distribution network voltage control is reviewed. • The relationships among the three artificial intelligence methods are systematically analyzed. • The existing algorithms, along with their strengths, limitations, and relationshipsare highlighted. • The research directions of artificial intelligence methods in distribution network voltage control are discussed in detail. [ABSTRACT FROM AUTHOR]

• A multistage reliability-constrained stochastic planning model is established for the diamond distribution network(DDN). • The Markov decision process is used to model the multistage stochastic dynamic decision process. • An approximate dynamic programming(ADP) algorithm is used to solve the model. In this paper, a multistage reliability-constrained stochastic planning model is established for the diamond distribution network, a new type of distribution system grid structure, with the goal of optimizing the total cost of investment and operation. The uncertainty of load growth is simulated by generating multiple load growth scenarios, and the power supply loss caused by the reliability of components in the system is also considered. The multistage stochastic dynamic decision process is modeled by The Markov decision process. In order to solve the "curse of dimensionality" problem in multi-stage stochastic planning model, the approximate dynamic programming algorithm is used to solve it. The case study is based on the typical structure of the diamond distribution network and realistic data of an actual district in Shanghai, China. The planning results verify the effectiveness of the model and the solution algorithm, and demonstrate the reliability and economy of the diamond distribution network are superior to the traditional double-ring network. [ABSTRACT FROM AUTHOR]

In field seismic exploration, missing seismic traces is inevitably encountered due to the constraints of the exploration environment and equipment. Thus, seismic data reconstruction is essential for seismic exploration analysis. In this paper, an attention-based U-net (AU-net) architecture is proposed by incorporating the attention mechanism into the U-net structure to address seismic data reconstruction challenges. The network incorporates both channel and spatial attention modules. Experiments comparing the reconstruction results of U-net, DnCNN, curvelet, and AU-net demonstrate the robustness of deep learning methods in handing increased missing trace percentages. The AU-net achieves superior reconstruction effect on contiguous missing regions, and exhibits better generalization through transfer learning experiments. To facilitate network training, this paper introduces a novel data-slicing technique to split and merge rectangular data for reconstructing shot records. This approach can be applied to any network and has high practical value. • A novel framework is built based on U-net for seismic data reconstruction in which attention module was added. • Transfer learning experiments proved the reliability of the network. • A novel splitting and splicing method was used to improved the quality of reconstruction. [ABSTRACT FROM AUTHOR]

Paleotemperature records were reconstructed for the past 13.3 kyr using the alkenone unsaturation index (U K′ 37 ) and the tetraether index of 86 carbon atoms (TEX 86 ) proxies measured in sediment core OKI-151, which was collected in the southern Okinawa Trough. The U K′ 37 - and TEX 86 -derived temperatures for the top sample are close to the modern mean annual sea-surface temperature (SST). Changes in SSTs in the southern Okinawa Trough were primarily controlled by the western tropical Pacific Ocean, low-latitude winter insolation, and sea-level rise. Unlike previous studies, we found that the high-latitude North Atlantic played no significant role in the SST variations in this area. Moreover, SSTs in the southern Okinawa Trough decoupled from the East Asian summer monsoon system in the last 13.3 kyr. The U K′ 37 - and TEX 86 -based SSTs dropped significantly at 7.6–6.9 kyr BP (centered on 7.3 kyr BP). These findings suggest that the cold event at 7.3 kyr BP was widely recorded in the Okinawa Trough. However, the TEX 86 -based SSTs dropped approximately 14 °C during this period for an unknown reason. [ABSTRACT FROM AUTHOR]

• A multi-timescale voltage control model is formulated to control different timescale regulators. • The control variables of these regulators are assigned to multiple agents. Through centralized training and decentralized execution, these agents can obtain optimal coordinated control strategy. • A MADRL-based method is proposed to obtain the control strategy, which is based on the MADDPG algorithm and spplies Gumbel-Softmax distribution to solve discrete actions. Nowadays a large number of distributed generators and controllable elements connecting to the distribution network have resulted in higher requirements for voltage control. Existing voltage control methods require a specific physical model and are time-consuming with the complexity increasing. To overcome these challenges, this paper proposes a multi-timescale voltage control scheme using multi-agent deep reinforcement learning (MADRL). Firstly, considering the control requirements of different timescale regulators, a multi-timescale voltage control model is formulated. Then the control variables are assigned to multiple agents, and a MADRL-based voltage control scheme is proposed, which is based on the multi-agent deep deterministic policy gradient (MADDPG) algorithm and applies Gumbel-Softmax distribution to solve discrete actions. Through centralized learning and decentralized execution, this scheme can obtain the optimal coordinated control strategy of multiple regulators adaptively and achieve the effect of distributed control. Finally, case studies are conducted on the modified IEEE-123 bus system, and the performance of the proposed method is compared with the conventional model-based optimal voltage control scheme and other DRL-based methods. The results show that the MADRL-based method possesses better performance than other methods. [ABSTRACT FROM AUTHOR]

The Kuroshio current transports large amounts of heat and water vapor into the South China Sea (SCS) through the Luzon Strait and plays a key role in modulating the surrounding hydroclimate. However, there is no detailed high-resolution history of the Kuroshio intrusion into the SCS preceding the Holocene. Here, clay mineral assemblages and Sr–Nd isotopic values (87Sr/86Sr and εNd) of core CS11 represent the relative abundance of Taiwan and Luzon fluvial sediment contributions in the SCS deep basin, which can be further used as proxies of relative variation of the Kuroshio intrusion into the SCS over the past 40 kyr. Combined with linear sedimentation rate (LSR) and results of previous studies, we demonstrate that variations of Kuroshio currents between the SCS and the open Pacific display opposing trends within each marine isotope stage, similar to the waxing and waning of its modern configuration. The El Niño–Southern Oscillation (ENSO) has acted as the key factor driving variations of the Kuroshio currents over the past 40 kyr. During late marine isotope stage (MIS) 3, the Kuroshio intrusion into the SCS gradually decreased due to decline in intensity of El Niño-like conditions, while an El Niño-like state favored the Kuroshio intrusion into the SCS during MIS 2, in particular during the Last Glacial Maximum (LGM) when Kuroshio transport in the open Pacific weakened. The Kuroshio intrusion into the SCS was largely sluggish in the early Holocene, when a La Niña-like condition prevailed, and then the Kuroshio intrusion was enhanced during the middle to late Holocene under the influence of increased El Niño frequency. • Kuroshio Intrusion is the key factor controlling sediments reaching deep basin of the NE SCS over the past 40 kyr. • ENSO drove distinct patterns of Kuroshio in the SCS and in open Pacific during each MIS, similar to the modern configuration. • El Niño-like conditions favored increasing Kuroshio intrusion into the SCS but decreasing the transport in the open Pacific. [ABSTRACT FROM AUTHOR]

Abstract: Using the measured capacitance–voltage (C–V) curves and current–voltage (I–V) curves for the prepared AlGaN/AlN/GaN heterostructure field-effect transistors (HFETs), the relationship between polarization Coulomb field scattering (PCF scattering) and the subthreshold swing for depletion mode (D-mode) AlGaN/AlN/GaN HFETs has been investigated. It was found that the S value (S=(∂lg(I DS )/∂V GS)−1) of subthreshold swing is smaller for the device with the stronger PCF scattering, and the S value decreases by more than 26% for the D-mode AlGaN/AlN/GaN HFET samples. The reason is attributed to the big gradient of the mobility and the gate-source bias curve which is generated by the PCF scattering. [Copyright &y& Elsevier]

Determination of the geochemical and mineralogical characteristics of coal can provide useful information on the geological setting and evolution of coal basins and assist in identifying factors that control the distribution of the minerals and elements of interest. The Late Permian coals of southwestern China have received much attention because some of these coals are usually considered to be potential sources of some critical metals and have high concentrations of potentially toxic elements. Mineralogical and geochemical analyses were carried-out on the Late Permian coals from the Kulishu and Sijichun mines of the Zhijin-Nayong Coalfield, Western Guizhou, China. The diagram of Al 2 O 3 /TiO 2 -Nb/Yb shows that the sediment source of the Kulishu and Sijichun coals is dominantly the Emeishan magmatic province with a smaller contribution from a Neoproterozoic metamorphic-granite complex, both of which are the two major components of the Kangdian Upland. The sediment source of the roof and floor rocks is dominantly basaltic volcanics in the Emeishan large igneous province (ELIP), while the partings were probably derived from eruptions of the Emeishan felsic-alkaline magmas and a mixture of ashes derived from a distal volcanic arc. Highly elevated total sulfur contents (dominated by pyritic and organic sulfur), abundant framboidal pyrite, as well as disseminated fine-grained pyrite provide evidence for input of seawater during the peat and coal formation. Paragonite mineralization with enrichment of Li, Nb (Ta), Zr (Hf), REY and Pb in the Sijichun coals and partings of the Kulishu coal are attributed to the intrusion of alkaline magma. The pyrite, quartz, albite, anatase and gypsum occurring as veins-, cleat-fillings and separate well-crystallized aggregates of epigenetic origin in the studied coals are indicative of the influence of hydrothermal fluids from a magmatic source. [ABSTRACT FROM AUTHOR]

Although the geochemical and mineralogical characteristics and provenance of Permian-Triassic boundary (PTB) widespread volcanic ashes from southern China have been well investigated, the volcanic ashes just prior to the end-Permian mass extinction (EPME) have rarely been studied. This paper presents the mineralogical and geochemical compositions of volcanic ashes from the latest Permian coal-bearing strata of southwest China. Based on the relative abundances of kaolinite and mixed-layer illite/smectite (I/S), the volcanic ashes in the present study can be divided into tonsteins and K-bentonites, which are dominated by kaolinite and I/S, respectively. The I/S in K-bentonites formed during burial diagenesis in a non-marine environment, indicated by their low contents of sulfur and low ratios of Sr/Ba. Based on the general geothermal gradient and vitrinite reflectance of coals, the I/S was deduced to have formed under a temperature less than 100 °C. Collectively, the occurrence of vermicular kaolinite, as well as high-temperature quartz and euhedral primary zircon identified in tonstein samples indicate an intermediate-felsic pyroclastic origin for the volcanic ashes, while rounded quartz and mica grains both in tonsteins and K-bentonites reflect the products of erosion from sediment source regions. The negative Eu anomalies, rare earth elements (REY) distribution patterns, low contents of Sc, V, Cr, Co, Ni and Zn, and Al 2 O 3 /TiO 2 values, suggest that the tonsteins and K-bentonites are related to felsic volcanic eruptions. The relationship between Al 2 O 3 /TiO 2 vs. Nb/Yb and Al 2 O 3 /TiO 2 vs. Zr/TiO 2 ratios indicate that the tonsteins and K-bentonites were derived from at least two felsic sources: (1) some distal volcanic arc(s) and (2) the top of the Kangdian Upland exposing the alkaline-felsic volcanic rocks formed during the waning activity of the Emeishan plume and the basement of the Kangdian Upland exposing older felsic rocks. • Seven volcanic ash layers were recognized in the latest Permian coal-bearing strata. • The volcanic ashes with felsic origin are recognized as tonsteins and K-bentonites. • The volcanic ashes were associated with the Emeishan plume and the volcanic arcs. [ABSTRACT FROM AUTHOR]

The coal-hosted Ge deposit (Early Cretaceous) at Wulantuga, Inner Mongolia, northern China, is one of the largest Ge deposits in the world. Although the origin, modes of occurrence, and spatial distribution of Ge in this deposit have been investigated by several studies, the provenance and pathways of Ge from the source to the deposit are largely unknown. In this study, we investigated the 87Sr/86Sr values in the high-Ge coal of the Wulantuga deposit and the stratigraphically-equivalent low-Ge coal of the No. 1 Pit, both from the Shengli Coalfield, Inner Mongolia, northern China. In addition to an organic association, Sr and Ca in the high-Ge and low-Ge coals also occur in gypsum. The water-soluble Sr (i.e., in gypsum) in the high-Ge coal (Ge concentrations: 45–1170 ppm, 273 ppm on average, whole coal basis) has 87Sr/86Sr values in the range of 0.710411 to 0.710633 (with an average of 0.710478). In contrast, the low-Ge coal (Ge concentrations: up to 4.23 ppm, 0.45 ppm on average, whole coal basis) has lower 87Sr/86Sr values in two sub-groups, a low range of 0.709896–0.71005 (with an average of 0.709736) and a high range of 0.710173–0.710547 (with an average of 0.710329 and dominantly in the range of 0.710173–0.710406). The higher 87Sr/86Sr values in the high-Ge coals indicate that the highly-elevated concentration of Ge is associated with a local source of radiogenic Sr. The enrichment of Ge in the coal is due to several consecutive processes. Surface waters penetrated deeply into granite and dissolved at least partially more soluble phases of the granite. The Ge-rich solution flowed over ground or underground into the Shengli Coalfield and Ge precipitated in the peat, the precursor of the coal investigated in the coalfield. The 87Sr/86Sr values of the water-soluble fraction, the elemental compositions of high-Ge and low-Ge coals, and the geomorphological setting of the coalfield point to the Hercynian granodiorite intrusion on the nearby SE margin of the Shengli Coalfield as the primary source of Ge in the Wulantuga coal-hosted Ge deposit. In addition to serving as an indicator of the mode of formation of the coal-hosted Ge deposit, the 87Sr/86Sr values and their spatial distribution can provide an indication for the hydrological pathways of the mineralising fluid. • The Sr in gypsum in the high-Ge coals has 87Sr/86Sr values from 0.710411 to 0.710633. • The Sr in gypsum in the low-Ge coal has lower 87Sr/86Sr values, 0.709896–0.710547. • The higher 87Sr/86Sr values in the high-Ge coals indicate a grantic Ge source. [ABSTRACT FROM AUTHOR]

• Surface pollen concentration is proportional to content of silt and clay. • Both Pinus and fern spores showed a gradual increase toward the deeper waters. • Yellow River input dominated the pollen provenance in the Bohai Sea. • Circulation are the main driving forces for pollen-spore transport. • Fluctuations of fossil Pinus and herbs revealed the sea level and climate changes. To elucidate the mechanisms responsible for pollen and spore transportation and deposition in the Bohai Sea, fully covered seafloor-surface sediment samples were collected for palynological and grain size analysis. The results reveal that the pollen and spore concentrations were higher in the head of Liaodong Bay and in the muddy area of the Bohai Sea. The Yellow River was the main source of pollen and spores in the Bohai Sea. The sediments with relatively high pollen concentrations consisted mainly of clay and fine silt, whereas sediment with lower pollen concentrations was mostly fine sand. In addition, the percentages of Pinu s pollen and pteridophyte spores increased with increasing sea water depth, while other arboreal (excluding Pinus) and herbaceous pollen generally decreased with increasing distance from the shore. The relationship between the pollen taxa and the water depth of the sampling points shows that the fluvial water plays a predominant role in pollen transmission within 20 m of water depth, while the wind is the main driving force for pollen transmission when the water depth exceeds 20 m. Although Pinus pollen and pteridophyte spores were over-represented, there was good correlation between marine pollen signals and terrestrial vegetation. Apart from the influence of rivers and wind on pollen and spore deposition, the tidal currents and circulation were also main force responsible for transporting sediment and determining the differentiation of pollen and spores in the Bohai Sea. The comparison of pollen and spore percentages between surface sediment and fossil records from sedimentary cores made it possible to identify changes in pollen sources and transport mechanisms. Meanwhile, the percentage fluctuations of fossil Pinus and herbaceous pollen revealed concomitant changes of the sea level and climate. These findings are of paramount importance to the interpretation of Quaternary marine pollen data from the Bohai Sea, China. [ABSTRACT FROM AUTHOR]

It is crucial to explore the intrinsic mechanisms that influence thermometric sensitivity. This study investigates the optical performance of materials with the same crystal structure but different phonon energies. Ln 2 O 2 S:Er 3+ /Yb 3+ (Ln = La/Gd/Y) phosphors with similar morphology and particle sizes were prepared to systematically study the influence of different phonon energy matrices on optical properties. The intrinsic mechanism was elucidated through the matching degree between the energy gap and phonon energy, Judd-Ofelt (J-O) theory, and quantum dielectric theory. It was ultimately concluded that the combination of high phonon energy with a large Ω 2 and a small Ω 6 is beneficial for enhancing the sensitivity of temperature sensing materials.

This research discusses that cognitive processes such as memory, attention and creativity differ in students and professionals, among musicians and non-musicians, dealing with musical performance. The purpose of the study was to evaluate and compare the role of memory, attention and creativity as cognitive processes in musical performance, focusing on the differences between non-musicians and musicians. The sample involved 400 individuals, students and professionals, specialising in music and economics. The research instruments used by the scholars were the Wechsler Memory Scale, the Conners Performance Test, and the Torrance Tests of Creative Thinking. Musical students possessed better-developed auditory and short-term memory, while professional musicians had better auditory, visual working and short-term memory. Analysis of attention reveals that music students score better than non-musicians on all four aspects: inattention, impulsivity, sustained attention, and vigilance. For professionals, the key aspects are impulsivity and sustained attention with better results revealed in musicians. Creative thinking was the only factor where the differences were statistically significant in all five scales and the findings proved that creativity was better developed among musicians. This study provides an in-depth analysis and adds new knowledge to existing literature and empirical data on the cognitive processes associated with musical performance, focusing on memory, attention and creativity. By examining the differences between non-musicians and musicians, as well as students and professionals, the study provides insight into how musical performance can be used as a way to develop these cognitive processes., (© 2024. The Psychonomic Society, Inc.)

A novel fluorescence chemical sensor-based probe 1-{[(E)-(2-aminophenyl)azanylidene]methyl}naphthalen-2-ol (AMN) was designed and synthesized, which performed a "naked eye" detection ability toward Cu 2+ and Co 2+ based on aggregation-induced emission (AIE) fluorescence strategy. It has sensitive detection ability for Cu 2+ and Co 2+ . In addition, the color changed from yellow-green to orange under the sunlight, realizing the rapid identification of Cu 2+ /Co 2+ , which has the potential of on-site visual detection under the "naked eye". Moreover, different "on" and "off" fluorescence expressions were exhibited under excessive glutathione (GSH) in AMN-Cu 2+ and AMN-Co 2+ systems, which could be employed to distinguish Cu 2+ from Co 2+ . The detection limits for Cu 2+ and Co 2+ were measured to be 8.29 × 10 -8 M and 9.13 × 10 -8 M, respectively. The binding mode of AMN was calculated to be 2:1 by Jobs' plot method analysis. Ultimately, the new fluorescence sensor was applied to detect Cu 2+ and Co 2+ in real samples (tap water, river water, and yellow croaker), and the results were satisfying. Therefore, this high-efficiency bifunctional chemical sensor platform based on "on-off" fluorescence detection will provide significant guidance for the advance development of single-molecule sensors for multi-ion detection.

Owing to the rapid development of wireless communication, radar and pulse power technology, the electromagnetic environment faced by electronic systems is increasingly complex and the intensity of electromagnetic field can be significant. In this study, a new interference phenomenon was observed when the microwave pulses were injected into the gallium nitride (GaN) high electron mobility transistor (HEMT) power amplifier through the output port. We investigated the relationship between the peak power of reverse injection microwave pulses and the duration or the amplitude of the interference by effect experiments. The interference duration could reach the magnitude of millisecond. Deep traps in GaN HEMT power amplifiers are proved to be the cause of this interference effects., (© 2022. The Author(s).)

Positive-intrinsic-negative (PIN) limiters are widely used to protect sensitive components from leakage power itself and adjacent high-power injection. Being the core of a PIN limiter, the PIN diode is possible to be burnt out by the external microwave pulses. Here, using a parallel computing program for semiconductor multi-physics effects designed by ourselves, we studied the influence of the thickness of the I layer and the anode diameter of the PIN diode on the maximum temperature change curve of the PIN diode limiter. The damage threshold criterion in the numerical simulation was first studied by comparing experimental results with simulation results. Then, we determined the impact of the structure on the thermal burnout effect induced by microwave pulses of PIN limiter diodes., (© 2022. The Author(s).)

Positive-intrinsic-negative (PIN) diodes are widely used as limiters to protect sensitive components from damage in radio frequency (RF) receiver systems and communication front-ends. However, PIN diode limiters can be burnt out due to the microwave pulses coupling through the front-end of RF receiver systems. The damage processes and mechanisms in PIN limiters are undoubtedly important topics. Here, the damage accumulation process in PIN limiters induced by external microwave pulses is studied via the injection experiments. The relationship between the degree of damage (i.e., insertion loss) in the limiters and number of the injected pulses is reported. The maximum temperature criterion for burnout in PIN limiters is theoretically predicted and experimentally verified not accurate, and it is further observed that the insertion loss of the PIN diode limiter changes significantly only if more energy is injected into the limiter via microwave pulses.