The Central Asian Orogenic Belt (CAOB) is the largest accretionary orogen in the world, which is responsible for considerable Phanerozoic juvenile crustal growth. The NE China and its adjacent areas ...compose the eastern segment of the CAOB, which is a key area for providing important evidence of the CAOB evolution and understanding the NE Asian tectonics. The eastern segment of the CAOB is composed tectonically of four micro-blocks and four sutures, i.e. Erguna block (EB), Xing'an block (XB), Songliao-Xilinhot block (SXB), Jiamusi block (JB), Xinlin-Xiguitu suture (XXS), Heihe-Hegenshan suture (HHS), Mudanjiang-Yilan suture (MYS) and Solonker-Xar Moron-Changchun-Yanji suture (SXCYS). The EB and XB were amalgamated by westward subduction, oceanic island accretions and final collision in ca. 500Ma. The XB and SXB were amalgamated by subduction-related Early Paleozoic marginal arc, Late Paleozoic marginal arc and final collision in the late Early Carboniferous to early Late Carboniferous. The JB probably had been attached to the SXB in the Early Paleozoic, but broken apart from the SXB in the Triassic and collided back in the Jurassic. The closure of Paleo-Asian Ocean had experienced a long continue/episodic subduction–accretion processes on margins of the NCC to the south and the SXB to the north from the Early to Late Paleozoic. The final closure happened along the SXCYS, from west Solonker, Sonid Youqi, Kedanshan (Keshenketengqi), Xar Moron River through Songliao Basin via Kailu, Tongliao, Horqin Zuoyizhongqi, Changchun, to the east Panshi, Huadian, Dunhua, Yanji, with a scissors style closure in time from the Late Permian-Early Triassic in the west to the Late Permian-Middle Triassic in the east. The amalgamated blocks should compose a united micro-continent, named as Jiamusi-Mongolia Block (JMB) after Early Carboniferous, which bounded by Mongo-Okhotsk suture to the northwest, Solonker-Xar Moron-Changchun suture to the south and the eastern margin of JB to the east.
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•Recent new data are reviewed, four blocks and four sutures have been recognized in the NE China, eastern CAOB.•A new tectonic model is suggested in the NE China.•Paleo-Asian Ocean is considered to be closed in the Late Permian-Middle Triassic.
•The study proposes a layered sharing architecture based on blockchain and federated learning, enhancing the security, accuracy, and efficiency of data sharing on Internet of Things devices.•The ...architecture enables model updates and security verification through client node clustering and blockchain consensus processes, ensuring reliable and secure data transmission.•Device clustering federated learning algorithm: A device clustering federated learning algorithm, based on label similarity, is designed to address the issue of imbalanced distribution of data labels. This algorithm improves the accuracy and stability of the system model.•High accuracy and low communication cost: Experimental results demonstrate that the research algorithm achieves 95 % accuracy after 30 iterations, with a relatively low communication cost. The system stability is also observed to increase with the number of label categories.•Improved efficiency in medical sharing system: In the context of a certain hospital's medical sharing system, the research system outperforms the original system by extracting information in 42.9 % less time while maintaining an accuracy of over 98 %. This highlights the effectiveness of the research methods in improving data transmission efficiency and accuracy in Internet of Things data sharing systems, with potential applications in other fields.
To share data on Internet of Things devices more securely, accurately, and efficiently, this study designs a layered sharing architecture based on blockchain and federated learning. This architecture achieves efficient and secure Internet of Things data sharing through client node clustering and blockchain consensus processes. In addition, to address the issue of imbalanced distribution of data labels in system devices, a device clustering federated learning algorithm based on label similarity is designed to improve the accuracy and stability of the model. The experimental results showed that under independent synchronous data distribution and non independent synchronous data distribution, the research algorithm achieved a 95 % accuracy after 30 iterations, and the communication cost was relatively low. When testing algorithm stability under non independent synchronous data distribution, the more label categories there are, the higher the accuracy. When the label category M = 12, the accuracy could reach 96.0 %. In the medical sharing system of a certain hospital, the research system took about 42.9 % less time to extract information than the original system, and the accuracy could be maintained at over 98 %. This research method can effectively solve the problem of uneven distribution of device data labels, and improve the data transmission efficiency and accuracy of Internet of Things data sharing systems. Moreover, this method can also reduce the impact of malicious nodes on the global model, providing technical support for data transmission and security protection in other fields.
Traditional epoxy resin materials are widely used in coatings, composite materials, electronic packaging materials, etc. They are usually made of unsustainable fossil resources and cannot be recycled ...under mild conditions. Degradable thermosetting resins with dynamic covalent structure provide a potential solution to this conflict. In this paper, using biomass energy vanillin, m-xylylenediamine and 1, 6-hexanediamine as raw materials, two dynamic imine bond curing agents were synthesized, and then cured with DGEBA to prepare two bio-based imine epoxy vitrimers. The thermal and mechanical properties of two imine epoxy vitrimers were studied and compared in detail. Results showed that the two types of polymers exhibit excellent thermal stability and solvent resistance. At the same time, the tensile strength, modulus and elongation at break were comparable to or even better than those of conventional bisphenol A epoxy resin. In addition, due to the hydrolysis of the dynamic imine bonds, vitrimers had degradable characteristic, and its degradation also exhibited temperature, solvent and acidity dependence. More importantly, the recyclable carbon fiber reinforced polymer composites made of these two vitrimers could be completely degraded under weak acid conditions, and the nondestructive recycling of carbon fiber composites could be realized. We envision that this vitrimers with simple process, excellent comprehensive properties and degradability will make it a potential candidate for applications in sustainable structural materials.
•This study assesses greenspace-mental health associations in various exposure contexts.•All measures of greenspace exposure in residential places are associated with mental health.•Only street ...view-based greenspace quality in recreational places is positively associated with mental health.•Both street view-based greenspace quantity and quality in participant’s mobility path are associated with mental health.
Natural environments especially greenspace may play an important role in enhancing people’s mental health. However, the existing literature mainly assesses greenspace exposure in people’s residential neighbourhood ignoring the dynamic nature of daily movements and residential histories. Also, most research assesses greenspace from an ‘over-head’ perspective whereas an ‘eye-level’ perspective may better capture people’s experiences of greenspace, including its quality. We examine the importance of capturing people’s eye-level greenspace exposure across different places people occupy in their everyday lives. We construct four measures of greenspace capturing overhead (NDVI), eye-level quantity and quality (Street View Greenness (SVG)) and self-reported neighbourhood greenness exposure. First, we assessed greenspace exposure in residential neighbourhoods, workplaces, recreational places, mobility path and previous residential neighbourhood. The four greenspace indicators were not associated with each other, suggesting they capture different aspects of greenspace. Second, we examine the associations between dynamic greenspace exposure and residents’ mental health using survey data collected from 26 neighbourhoods of Guangzhou, China. The results show that all measures in residential places are associated with mental health. However, only SVG-quality in recreational places is positively associated with mental health, while both SVG-quantity and SVG-quality in participant’s mobility path are associated with mental health. Our findings demonstrate eye-level greenspace quality is more important in relation to mental health. Policymakers and planners should focus not only on residential neighbourhoods, but also consider the wider environments that people encounter in their everyday lives.
Rubber material is an excellent cushioning material in daily life and engineering applications. In this paper, the influence of rubber combination types and the corrugated surface roughness on ...cushioning performance are analyzed. By controlling the friction coefficients at different positions, the influence on the cushioning performance is also explored. Solving the numerical instability and energy nonconservation that are prone to occur in collisions is crucial for the accuracy of numerical simulation. The complexities of collision solution are overcome by separating nonlinear factors. The dynamics equation is derived according to the principle of virtual displacement, the geometric nonlinear problem of materials is described by the total Lagrangian formulation. Under the bipotential framework, the boundary nonlinear problem is solved based on the complete contact law. To reduce the solution cost and to improve the numerical accuracy, the prediction-correction step is used to solve the collision force. The bipotential coefficient is automatically updated with time steps, without the need for manual adjustment by users, achieving better convergence. Then, the collision force is substituted into the dynamic equation in the form of external load, which will not increase the degrees of freedom, and has better numerical robustness. In addition, the Newton–Raphson iterative method is embedded in the Tamma–Namburu scheme to solve the material nonlinearity problem and improve the numerical stability. Several numerical examples are presented to demonstrate the effectiveness of the proposed algorithm in the simulation of collision problems. Moreover, the proposed algorithm is proved to be stable and strictly satisfy the law of energy conservation/dissipation. Even for the corrugated surface structure with nonuniform friction, it can also better complete simulating the collision process.
As a paradigm of greenhouse climate in Earth's history, the Cretaceous provides significant rock records of global climate changes under conditions of greenhouse climate. The Songliao Basin, among ...the longest duration (85–90m.y.) of continental sedimentary basins, provides an excellent opportunity to recover a nearly complete Cretaceous terrestrial sedimentary record. Extensive lake deposits, ten-kilometers deep and covering an area of 260,000km2 of the Songliao Basin, provide unique, detailed records that can be tied to the global stratigraphic time scale, thereby improving our understanding of the continental paleoclimate and ecological system. The two coreholes at SKIs and SKIn sites were drilled into this basin and completed with a total length of 2485.89m of recovered core that spanned the complete middle-to-Upper Cretaceous strata in the basin. The unique geological setting of long-term continuous subsidence within the largest Cretaceous landmass in the world — makes the Cretaceous Songliao Basin of northeastern China an ideal place to study Cretaceous climate change on the continent. This paper reviews the literature on the paleogeography and paleoclimate of the northern East Asia and the Songliao Basin during the Cretaceous. Based on the climatologically sensitive deposits, oxygen isotope studies, and paleontology, the climate during the Cretaceous in the Songliao Basin was temperate and humid with relatively abundant rainfall. During the period, significant changes – four cooling, three warming, and three semiarid events – are generally consistent with the oxygen isotope data from East Asia, and the four cooling events, in Berriasian–Valanginian, Aptian–Albian, early Santonian, and Campanian–Maastrichtian, may be related to potential glaciations in Cretaceous.
► We analyze the Cretaceous paleogeography and paleoclimate in the Songliao Basin. ► The basin located in the Northern Hemisphere middle latitude spans up to 85–90m.y. ► Tectonic activity and water supply controlled the character of sediment facies. ► The climate of the basin was temperate and humid with relatively abundant rainfall. ► There were four cooling, three warming and three semiarid events in the Cretaceous.
The Central Asian Orogenic Belt (CAOB) is the largest accretionary orogen in the world with considerable Phanerozoic juvenile crustal growth. The eastern segment of the CAOB is occupied by NE China ...and its adjacent areas, which locates in a triangle area surrounded by Siberian Craton to the northwest, North China Craton (NCC) to the south and Pacific oceanic plate to the east. Therefore, the NE China is a key area to study the geological evolution of multiple tectonic systems and overprinting, which has become a hot research topic. In the past five decades, especially the last two decades, there have been many detailed geological investigations carried out and a lot of new data reported in NE China. A progress has been achieved in tectonic evolution, however, there are still many open questions and arguments dealing with the tectonic models, correlation of tectonic units, amalgamation of different blocks and their tectonic affinity. In this study, we did a detailed review of the tectonic evolution of NE China and regional comparison and correlation of the different tectonic units in the eastern segment of CAOB. We re-subdivided NE China into two old blocks of Erguna block (EB) and Jiamusi block (JB) with Precambrian basement and three accretionary terranes of Xing'an accretionary terrane (XAT), Songliao accretionary terrane (SAT) and Zhangguangcai accretionary terrane (ZGCAT), which are separated from each other by the Xinlin-Xiguitu suture (XXS), Hegenshan-Heihe suture (HHS), Longfengshan suture (LFS) and Mudanjiang-Yilan suture (MYS), respectively. The ZGCAT is dominantly composed of early Paleozoic magmatic arc materials and minor late Paleozoic igneous rocks with an old Yichun mini-block, while the SAT consists dominantly of the late Paleozoic magmatic rocks with two small old blocks of the Xilinhot and Longjiang mini-blocks. According to the tectonic correlation and comparation of different tectonic units, we established a new orocline tectonic model for the eastern CAOB: 1) the XAT and ZGCAT accreted to the southern (present position) margin of Ereendavaa-Erguna-Mamyn block (EEMB) and Bureya-Jiamusi-Khanka block (BJKB) with the closure of Xinlin-Xiguitu-Heilongjiang ocean during the early Paleozoic; 2) Subsequently, the SAT accreted to the southern (present position) margin of integrated XAT-ZGCAT terrane with the closure of Hegenshan-Nenjiang-Longfengshan ocean during the late Paleozoic. These initially W-E linear shaped accretionary orogenic belts were ultimately bent southward through Paleozoic time and constituted a huge Paleozoic orocline, NE China Orocline, which collided with NCC by a scissor-like style closure of Paleo-Asian Ocean (PAO) from west to east along the Solonker-Xar Moron-Changchun-Yanji suture (SXCYS) during the late Permian-middle Triassic. The NE China Orocline, together with Tuva-Mongol Orocline and Kazakhstan Orocline in the western CAOB, constituted a huge multiple orocline tectonic system in the CAOB during the Paleozoic era. Our study will contribute to the understanding on tectonic evolutions of CAOB and the NE Asian, and suggests that the orocline should be a common tectonic model for accretionary orogeny.
•NE China consists of two Precambrian blocks and three Paleozoic accreted terranes.•A new orocline tectonic model is established for first time in NE China.•Blocks in NE China had been integrated in later Early Carboniferous.
The category of not in employment, education or training (NEET) refers to young people who are recorded as neither in paid employment nor formal education either at one time point, or for a ...continuous period. This article assesses levels of employment scarring for those aged 36–39, at Census 2011 (prime employment years) who were recorded as NEET when aged 16–19 at Census 1991 in Scotland. Outcomes are compared for those who moved from NEET into economic activity and by gender. We find evidence that NEET status leads to long-term scarring associated with economic inactivity and unemployment and that this is only partially offset for those who moved from NEET in 1991 to be economically active in 2001. The results also highlight gendering of NEET outcomes. NEET may be a category borne of administrative convenience, rather than sociological consistency but, as intended, it captures a group who experience disadvantage.
The increase in surface air temperature in China has been faster than the global rate, and more high temperature spells are expected to occur in future. Here we assess the annual heat-related ...mortality in densely populated cities of China at 1.5 °C and 2.0 °C global warming. For this, the urban population is projected under five SSPs, and 31 GCM runs as well as temperature-mortality relation curves are applied. The annual heat-related mortality is projected to increase from 32.1 per million inhabitants annually in 1986-2005 to 48.8-67.1 per million for the 1.5 °C warming and to 59.2-81.3 per million for the 2.0 °C warming, taking improved adaptation capacity into account. Without improved adaptation capacity, heat-related mortality will increase even stronger. If all 831 million urban inhabitants in China are considered, the additional warming from 1.5 °C to 2 °C will lead to more than 27.9 thousand additional heat-related deaths, annually.
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•Songliao Basin, NE China, initiated as a backarc rift in the late Jurassic.•Songliao Basin evolved to a foreland basin after 88 Ma due to changing plate dynamics.•Songliao foredeep ...progressively deformed after 81.6 Ma, as Songliao evolved to a wedge-top basin.•Much of Songliao foreland basin evolved into the orogenic wedge and eroded by 65 Ma.
Songliao Basin, the largest Mesozoic intracontinental nonmarine basin in eastern China, initiated during the latest Jurassic as a backarc extensional basin; rifting failed and thermal cooling controlled subsidence through the early Late Cretaceous. Integrating 2-D and 3D reflection seismic and borehole data with regional geological studies, we interpret sedimentary sequence and structural patterns of the Coniacian-Maastrichtian fill of Songliao Basin as defining a retroforeland basin system developed after 88 Ma (marked by the T11 unconformity in the basin), including (1) significant increase in the thickness of the Nenjiang Formation eastward towards orogenic highlands of the Zhangguangcai Range and the convergent continental margin; (2) a shift of detrital provenance in the basin from north to southeast; and (3) propagation of E-W shortened structures, increasing eastward in amplitude, frequency, and degree of inversion toward the orogen. During latest Cretaceous, foreland basin fill progressively deformed, as the foredeep evolved to a wedge-top tectonic setting, marked by the basin-wide T04 unconformity within the upper Nenjiang Formation at 81.6 Ma. Much of the basin was brought into the orogenic wedge and eroded by the end of the Cretaceous. Late Jurassic/Early Cretaceous backarc rifting of uncratonized basement comprised of accreted terranes likely facilitated and localized the foreland. Synrift normal faults reactivated and extensively inverted as thrust faults are prominent in the eastern 1/3 of the basin, whereas folds developed above detachments in shaley early post-rift strata dominate the western 2/3 of the basin. Songliao foreland development likely was driven by changing plate dynamics and collision along the Pacific margin after 88 Ma.
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