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The MT profile starts in the south at Shuanghu in northern Qiangtang, crosses the Jinsha River suture, and extends to the south of Jingyu Lake, with a total length of 350 km. In 2020, 65 broadband MT and 15 long-period MTstations collected data along the profile, with each LMT station reoccupying the location of a BMT station. The average spacing between BMT stations was 5 km and between LMT stations was 20 km. The BMT stations used MTU-5 instruments (Phoenix Geophysics, Canada) to collect data for more than 24 h, and the LMT stations used Lemi-417 instruments (Lemi, Ukraine) to collect data for 5–7 days. The three mutually orthogonal magnetic field components (Hx, Hy, and Hz) and the two mutually orthogonal horizontal electric field components (Ex and Ey) were estimated for each measuring station, where x, y, and z indicate the north–south, east–west, and vertical directions, respectively.

In recent years, research progress in terahertz devices has affected the development of terahertz communications. In this article, an asymmetric metamaterial coated with the GaAs layer is proposed ...

Recently, two-dimensional Transition metal dichalcogenides (TMDCs) have attracted widespread attention due to their unique electrical and optical properties. Specially, the monolayer WS2 has high p...

Li-rich layered oxides (LLOs) are promising cathodes for lithium-ion batteries because of their high energy density provided by anionic redox. Although great improvements have been achieved in electrochemical performance, little attention has been paid to the energy density stability during fast charging. Indeed, LLOs have severe capacity fading and voltage decay especially at a high state of charge (SOC), disabling the application of the frequently used constant-current-constant-voltage mode for fast charging. Herein, we address this problem by manipulating the external electric field and tensile strain induced by lattice expansion effect in nanomaterials under the guidance of theoretical calculations, which indicate that LLOs at high SOC have almost a zero band gap and a low oxygen formation energy. This strategy will weaken polarization, stabilize lattice oxygen, and restrict phase transition simultaneously. Thus, the energy density during fast charging can be highly stabilized. Therefore, it may be of great value for the practical application of layered cathodes.

The three-dimensional (3-D) electrical structure of the upper-mantle was used to examine the deep origins of and relationship among the Cenozoic volcanoes located in Northeast China (NEC). High-quality, long-period magnetotelluric (LMT) full-impedance tensor data were collected in NEC and subjected to 3-D Gauss-Newton inversion in order to construct a resistivity model. The resulting model reveals the presence of multiple localized low-resistivity anomalies (LRAs) within the high resistivity lithosphere beneath NEC. These LRAs partially coincide with Cenozoic volcanoes on the surface. Three LRAs that form a larger, annular LRA were observed in the deep upper mantle beneath the Songliao Basin, whereas vein-like LRAs were found in the asthenosphere that connect the lithosphere and deep upper mantle. Petrophysical analyses suggest that the LRAs may have been caused by fluid-induced melting. Based on our electrical model, we propose that, following dehydration of the subducted Western Pacific slab into the mantle transition zone (MTZ) beneath NEC, the released water migrated upward and caused partial melting at the top of the MTZ beneath the Songliao Basin. Under the effect of buoyancy, the melted mantle formed a thermal upwelling that caused melting of asthenosphere before diapiring at the base of the dry lithosphere. The magma then penetrated structural boundaries (such as thinner, weaker, or activated suture zones) and finally reached the Earth’s surface. This melting and upwelling of hot mantle materials may have resulted in large-scale volcanism in the region throughout the Cenozoic, including the eruption of Changbai Mountain and Halaha Volcanoes. Our results suggest that the Cenozoic NEC volcanoes may all share a similar mode of genesis, and probably originated from the annular LRA in the deep upper mantle.

Soft manipulator is more safe than rigid manipulator when working with people, but it’s also more difficult to design and control. Unlike some existing works establishing kinematic model with static analysis, the kinematic model is established by using piecewise constant curvature methods and is divided into two subsystems. For the purpose of promoting the shape control for soft manipulators, an adaptive control scheme is proposed for the soft manipulator in this paper. In the framework of dynamic state feedback, the unknown function can be approximated by neural network (NN), and therefore an adaptive controller is devised. Furthermore, it is proven that the output tracking errors satisfy the stipulated performance by applying the time-varying barrier Lyapunov function. Finally, the simulation illustrates the rationality of the proposed control scheme.

Lithium-rich layered oxides always suffer from low initial Coulombic efficiency, poor rate capability and rapid voltage fading. Herein, engineering oxygen vacancies in hierarchically Li1.2Mn0.54Ni0.13Co0.13O2 porous microspheres (L@S) is carried out to suppress the formation of irreversible Li2O during the initial discharge process and improve the Li+ diffusion kinetics and structural stability of the cathode mateiral. As a result, the prepared L@S cathode delivers high initial Coulombic efficiency of 92.3% and large specific capacity of 292.6 mA h g−1 at 0.1 C. More importantly, a large reversible capacity of 222 mA h g−1 with a capacity retention of 95.7% can be obtained after 100 cycles at 10 C. Even cycled at ultrahigh rate of 20 C, the L@S cathode can deliver stable reversible capacity of 153 mA h g−1 after 100 cycles. Moreover, the full cell using L@S as cathode and Li4Ti5O12 as anode exhibits a relatively high reversible capacity of 141 mA h g−1 with an outstanding voltage retention of 97% after 400 cycles at a large current density of 3 C. These results may shed light on the improvement of electrochemical performances of lithium-rich layered oxides via the multiscale coordinated design based on atomic defects, microstructure and composition.

The advantages of enclosed ground flare (EGF) contain that emissions of combustion in a timely manner, safe and reliable, complete combustion, low noise, to meet environmental protection. So EGF has become one choice of more chemical plants. However the EGF still belongs to the new technological means, the strength design of the flare system and the safety distance still do not have the standard requirement. Therefore, this paper research on the development process of the exhaust gas explosion caused by the EGF. Firstly, using PHAST software to simulate the damage caused by the flare gas leakage outside the abnormal condition. This is the determination of the safety distance of the EGF effect. And then using Hazard and Operability Analysis (HAZOP), Layer of Protection Analysis (LOPA), and Fault Tree Analysis (FTA) failure model for Safety Integrity Level (SIL) verification, demonstrate the installation of Safety Instrumentation System (SIS) to protect the Safety Instrumented Function (SIF) circuit to meet the safety requirements. This paper is conducive to the wind wall and the flare system of various types of material strength design and the surrounding personnel and facilities to determine the safety distance.

Lithium-rich layered oxide materials are considered as one of the most promising cathodes for high-energy lithium-ion batteries. However, their practical applications are currently restricted by its low initial Coulombic efficiency and poor rate capability and cycling stability. In this study, we report the preparation of Li1.2Mn0.54Ni0.13Co0.13O2 nanowires that have porous structures with different contents of spinel phase via a co-precipitation method followed by carefully controlled calcination steps. Structural characterizations verify that the as-prepared nanowires are composed of interconnected nano-sized subunits with porous structures, and spinel phases are embedded inside the layered structure. The electrochemical measurements show that the Li1.2Mn0.54Ni0.13Co0.13O2 nanowires bearing moderate content of spinel phase exhibit a high capacity of 291 mAh g−1 at 0.1 C and excellent capacity retention of 91.8% after 200 cycles at 1 C. The results also demonstrate that electrochemical performance of the Li1.2Mn0.54Ni0.13Co0.13O2 nanowires is influenced by the content of spinel phase which can be readily tuned by changing the heating rate in the calcination step. The combination of one-dimension porous structures and built-in spinel domains in Li1.2Mn0.54Ni0.13Co0.13O2 nanowires improves the electrolyte contact and Li+ diffusion, and restrains structural degeneration.

In recent years, the limited tuning ranges and selections of active materials in tunable terahertz metamaterials severely restrict their wide applications in tunable terahertz devices. In t...

The phase transition of Li-rich cathode materials occurred from surface to internal bulk structure leads to a poor stability of cycling performance, which seriously limits the development of the materials. Herein, with a facile designed hydrothermal method, the Li-rich layered oxides microspheres with the internal spinel phase are synthesized successfully. Compared with traditional hydrothermal method, a new heterostructured material exhibits high specific capacity remarkable cycling performance (247 mA h g−1 at 0.5 C) with high energy density (852 Wh kg−1). Under galvanostatic charge-discharge pattern, the discharge capacity retains about 91.5% after 300 cycles at a large current of 2 C. The full cell fabrication with artificial graphite as an anode and the synthesized heterostructured Li1.2Mn0.54Co0.13Ni0.13O2 material as cathode exhibits the favorable property and the practical applicability. We expect that this strategy is going to pave new ways to accelerate the property and application of Li-rich cathode oxides materials.

An amorphous CoSnO3@rGO nanocomposite fabricated using a surfactant-assisted assembly method combined with thermal treatment served as a catalyst for non-aqueous lithium-oxygen (Li-O2) batteries. In contrast to the specific surface area of the bare CoSnO3 nanoboxes (104.3 m2 g–1), the specific surface area of the CoSnO3@rGO nanocomposite increased to approximately 195.8 m2 g–1 and the electronic conductivity also improved. The increased specific surface area provided more space for the deposition of Li2O2, while the improved electronic conductivity accelerated the decomposition of Li2O2. Compared to bare CoSnO3, the overpotential reduced by approximately 20 and 60 mV at current densities of 100 and 500 mA g−1 when CoSnO3@rGO was used as the catalyst. A Li-O2 battery using a CoSnO3@rGO nanocomposite as the cathode catalyst cycled indicated a superior cyclic stability of approximately 130 cycles at a current density of 200 mA g–1 with a limited capacity of 1000 mAh g–1, which is 25 cycles more than that of the bare amorphous CoSnO3 nanoboxes.

This paper mainly introduces the modeling based on Cosserat rod theory and focuses on the adaptive neural network controller design based on model. In dealing with the external interference with the environment and the unmodeled dynamics of the system, a neural network (NN) is introduced to compensate it, and using Backstepping method to design the adaptive controller, finally the stability of the closed-loop system and the convergence of the signal in the system is proved with Lyapunov function theory, ensuring the end of the manipulator can track the given signal. In addition, the simulation experiment of soft manipulator swing and constant angle tracking control are carried out, and the simulation shows the rationality of the proposed controller.

Environmental audit is inevitably linked to climate change, one immediate target of the auditors is likely to be climate control, and the warming of the Earth and the consequent climatic changes affect us all. What is the link between environmental audit and climate change? What ties together some of these themes between environmental audit and climate change? The interaction between climate change and environmental audit has been one of the most challenging. In this paper, a scientometric analysis of 84 academic publications between 2013 and 2021 related to climate change and environmental audit is presented to characterize the knowledge domain by using the CiteSpace visualization software. First, we present the number of publications, the number of citations, research categories, and journals published through Web of Science database. Secondly, we analyze countries, authors, and journals with outstanding contributions through network analysis. Finally, we use keyword analysis and apply three types of knowledge mapping to our research, cluster view, timeline view, and time zone view, revealing the focus and future directions. We identify the most important topic in the field of climate change and environment audit as represented on the basis of existing literature data which include the Carbon Emissions, Social Capital, Energy Audit, Corporate Governance, Diffusion of Innovation Environmental Management System, and Audit Committee. The results show that climate change and environmental audit publications grew slowly, but the research are widely cited by scholars. Published journals are relatively scattered, but the cited journals are the world’s top journals, and most research countries are developed countries. The most productive authors and institutions in this subject area are in UK, Australia, USA, Spain, and Netherlands. There are no leading figures, but the content of their research can be divided into six clusters. Future research content involving city, policy, dynamics, information, biodiversity, conservation and clustering social capital, diffusion of innovation environmental management, and audit committee are the directions for future research. It is worth noting that cities, policies, and adaptability are closely linked to public health.

The creation and evolution of the Songliao Basin is closely related to the closure of the Paleo-Asian Ocean and the Mongolia-Okhotsk Ocean, and the subduction of the Paleo-Pacific Ocean. In an atte...

The Central Asian Orogenic Belt (CAOB) is the largest accretionary orogenic belt in the world. The Songnen and Jiamusi blocks, which are located along the eastern segment of the CAOB, form a complex structure influenced by the Mudanjiang ocean closure and the Paleo-Pacific plate subduction. Constraints on the deep structure of the Songnen and Jiamusi blocks are critical for studying the evolution, transformation and current activity of the CAOB. This study presents an analysis and interpretation of a 450-km-long magnetotelluric profile that imaged the deep lithospheric structure of these two blocks. The best-fit three-dimensional resistivity model, based on the nonlinear conjugate gradient algorithm, highlights the key lithospheric structures. The results show that the lithosphere beneath the Lesser Xing'an Range in the Songnen block is characterized by a high-resistivity structure, which is mainly related to the granite formed in multiple stages. The crust forming the Sanjiang basin in the Jiamusi block possesses a high–low–high resistivity structure in the transverse direction, corresponding well to the tectonic units. The low-resistivity structure of the Fujin uplift extends to the mantle, which represents mantle material that intruded the crust. There is a low-resistivity structure beneath the suture zone of the two blocks that is homologous with the large-scale low-resistivity anomaly beneath the basin and is related to the subducted Paleo-Pacific plate. Strong dehydration at the inflection point of the plate reduces the solidus temperature of the mantle material, resulting in melt and upwelling of mantle material. The Jiamusi block can be divided into southern and northern parts, possessing different structures. The southern part represents an original part of either the Gondwana continent or Tarim craton. The Sanjiang basin, in the northern part, has been heavily influenced by the subducted Paleo-Pacific plate, and is a region of strong activity.

The eastern segment of the Qilian orogenic belt, composed of the Linxia block and the Longzhong block, is located at the northeastern margin of the Qinghai–Tibet Plateau. The area has experienced multiple tectonic events, such as the closure of the Qilian Ocean, the convergence of the North China block and the Qilian terrane, and the collision of the Indian and Eurasian plates, forming a complex tectonic framework. To investigate the geological evolution of the area and the current location of the suture between the plates, we performed three-dimensional inversion of magnetotelluric data acquired along two profiles in the eastern segment of the Qilian orogenic belt using a nonlinear conjugate gradient algorithm to obtain electrical resistivity structure models to 60-km depth. The results include three key findings. (1) The Linxia block was originally a Japanese-type island arc with a mainly low-resistivity structure, which corresponds to deformed, fractured middle and lower crust that contains saline fluids. (2) The Longzhong block was originally a Mariana-type island arc and has a resistive structure with good integrity, consistent with crust composed of ocean island basalt. (3) The Maxianshan fault, shown as a belt with a steep gradient in electrical resistivity model, is a supracrustal fault that acts as a suture between the Japanese-type island arc (now the Linxia block) and the Mariana-type island arc (now the Longzhong block).

The electrical resistivity tomography (ERT) has the characteristics of low cost, high efficiency, rich information, non-destructive exploration, and large detection depth. At present, it is being widely used in archaeological exploration. It can provide a more accurate result whether it is the preliminary survey delineation or the later detailed exploration. Chengsijiazi ancient city, located at the bank of Tao’er river, was built during the Liao and Jin dynasties. Except for the western wall destroyed by the river, the rest of the city walls were well preserved. The main target body of this survey is a part of wall foundation of an ancient building in the ancient city ruins. The ERT data are acquired along 55 survey lines and the horizontal differential field line method is introduced to interpret the inversion results of the measurement data. The horizontal differential field line method could more accurately describe the structure and boundary characteristics of the target body. The ancient building wall foundation is characterized by obvious high-gradient dense field line, so that we can accurately delineates the position of the wall base, which was excavated by archaeologists and has been verified.

The Qilian Shan is located along the northeastern margin of the Tibetan Plateau, which is a key area for studying the growth and expansion of the Tibetan Plateau. There have been several geodynamic models developed to explain the deformation pattern of the Tibetan Plateau extending to the northeast, but they remain controversial. The magnetotelluric (MT) method can study subsurface electrical conductivity and rheological properties. A dense broadband and long period magnetotelluric (MT) profile across the middle Qilian Shan has been completed. The MT profile starts from the northeastern margin of the Qaidam Basin, crosses the Qilian Shan and Hexi Corridor, and finally reaches the southwestern margin of the Alashan Block. Based on data analysis results, a three-dimensional (3-D) resistivity model of the crust and upper mantle has finally been obtained. The MT results show that a relatively low resistivity zone exists at the bottom of the upper crust of the Qilian Shan, features as an intracrustal decollement, which indicates the decoupling deformation between the upper and lower crust. The isolated conductive bodies in the middle-lower crust of the Qilian Shan may have formed during the primary stage of plateau growth, suggesting that there may be no existence of the middle-lower crustal flow beneath the Qilian Shan. The Alashan Block lithospheric mantle may have partly underthrust southward the Northeastern Tibetan Plateau. The Tibetan Plateau may have grown and expanded northeastward across the Hexi Corridor to the Heli Shan Fault.