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For the vacuum preloading foundation treatment project, water covering construction is often carried out during vacuum pumping. It is very inconvenient for the monitoring personnel to measure the readings in the water with layered settlement instruments and equipment. This paper introduces an assembly method of foundation layered settlement monitoring device, including the assembly process of the monitoring device itself and the assembly process of embedding the monitoring device in the foundation. It has the advantages of simple structure, simple installation and stable data. It can realize the in-situ monitoring of different foundations, save manpower and material resources, and greatly improve the monitoring efficiency and accuracy.

Noise and noise propagation are inevitable and play a constructive role in various biological processes. The stability of cell homeostasis is also a critical issue. In the unidirectional transition cascade of colon cells, stem cells (SCs) are the source. They differentiate into transit-amplifying cells (TACs), and TACs differentiate into fully differentiated cells (FDCs). Two differentiation processes are irreversible. The stability factor is introduced so that the noise propagation mechanism from the perspective of stability is studied according to the noise propagation formulas. It is found that the value of the stability factor corresponding to the minimum noise in FDCs may be the best choice to enable colon cells to maintain high stability and low noise of the cascade. Moreover, for the source cell, the total noise only includes intrinsic noise; for the downstream cell with self-proliferation capability, the total noise mainly depends on its intrinsic noise and transmitted noise from upstream cells, and its intrinsic noise is dominant. For the downstream cell without self-proliferation capability, the total noise is mainly determined by transmitted noises from upstream cells, and there is a minimum value. This work provides a new approach for studying the mechanism of noise propagation while considering the stability of cell homeostasis in biological systems.

In the process of power operation, the correct identification of tools can lay a foundation for the detection of violations in power operation. In order to realize the recognition of power instruments, based on the current Yolo V5 algorithm, a detection algorithm for power instruments is proposed by improving Yolo V5 algorithm. Firstly, the model of Yolo V5 algorithm is introduced. Then the establishment of the power tool database and the process of model training are analysed. Finally, the test results are analysed and evaluated. The models generated after training were accelerated by TensorRT and then deployed on Jetson Xavier NX.

Iron chalcogenides are of particular interests among iron-based superconductors due to their distinct properties such as high-T c on FeSe monolayer and competing magnetic correlations in Fe1+y Te. Here we report unusual transport properties observed near the critical composition of Fe1+y Te (y ∼ 0.09) where competing magnetic correlations exist. The resistivity exhibits surprising temperature-dependent relaxation behavior below T N, resulting in the increase of resistivity with time for 35 K < T < T N, but the decrease of resistivity with time for 10 K < T < 35 K. Such resistivity relaxation is intimately coupled to the magnetization relaxation and can be attributed to the glassy magnetic states induced by the competing magnetic orders. These findings demonstrate strong coupling between itinerant carriers and local ordered moments in Fe1+y Te.

Unconventional superconductivity, in particular, in noncentrosymmetric systems, has been a long-sought topic in condensed matter physics. Recently, Re-based superconductors have attracted great attention owing to the potential time-reversal symmetry breaking in their superconducting states. We report the superconducting properties of noncentrosymmetric compounds Ta x Re1 – x with 0.1 ≤ x ≤ 0.25, and find that the superconducting transition temperature reaches a maximum of ∼8 K at the optimal level x = 0.15. Nevertheless, muon-spin rotation and relaxation measurements reveal no time-reversal symmetry breaking existing in its superconducting state, which is in sharp contrast to both centrosymmetric Re metal and many other noncentrosymmetric Re-based superconductors.

The hydraulic servo control system of the ground motion parameter field test system is introduced in this paper. The hydraulic servo control system mainly includes the seismic wave generating equipment system and the servo control system. And the equipment system consists of the P-wave and the S-wave generator. The main advantage of the hydraulic servo control system is that P-wave and S-wave generator can generate both p-wave and S-wave. The seismic waves produced are characterized by strong stability and high energy, which can overcome the shortcomings of instability, less energy and poor repeatability of the on-site wave generating device. It is necessary to generate the waveform of different types of seismic waves, such as sine wave, cosine wave, square wave and random wave. The vibration frequency of the seismic wave can be controlled to meet the actual demand of the seismic wave in engineering. The hydraulic servo control system can be run stably for a long time, without interference and unreliable operation in various environments and states, which can be of great significance for the seismic safety evaluation of the engineering site.

Inconceivably large changes (up to 106%) of the resistivity induced by external magnetic field—a phenomenon known as the extreme magnetoresistance effect has been reported in a great number of exotic semimetals. The very recent and exciting discoveries mainly pay attention to the compounds without magnetic ground states, which appears to limit the potential growth of semimetal family. For fundamental scientific interests, introduction of spin degree of freedom would provide an almost ideal platform for investigating the correlation effect between magnetism, crystallographic structure and electric resistivity in materials. Here, we report the experimental observation of metamagnetic behaviors and transport properties of HoBi single crystals. Being a magnetic member of the rare earth monopnictide family, the magnetoresistance of HoBi is significantly modulated by the magnetic orders at low temperature, which shows a nonmonotonic increment across the successive magnetic phases and reaches 104% (9 T and 2 K) in the ferromagnetic state. Kohler’s rule predicts that more than one type of carriers dominates the transport properties. Well fitted magnetoresistance and Hall resistivity curves by the semiclassical two-band model suggest that the densities of electron and hole carriers are nearly compensated and the carrier mobilities in this compound are ultrahigh. Besides, the inverted band structures and nonzero Z 2 topological invariant indicate that possible nontrivial electronic states could generate in the ferromagnetic phase of HoBi. Combining the experimental and theoretical results, it is found that the cooperative action of carrier compensation effect and ultrahigh mobility might contribute to the extreme magnetoresistance observed in the titled compound. These findings suggest a paradigm for obtaining the extreme magnetoresistance in magnetic compounds and are relevant to understand the rare-earth-based correlated topological materials.

In this paper, we report the simultaneous fabrication of nanogratings and three-dimensional (3D) concentric circles in the same bulk of ZnO single crystal by femtosecond laser irradiation of a single spot. For nanogratings, polarization dependence and selective growth characteristics are two main characteristics; for 3D concentric circles, a noticeable feature is their close relationship with the development of the deep crater ablated by the femtosecond laser. On the basis of the above key points observed from scanning-electron-microscope (SEM) images, possible formation mechanisms for these nanostructures are analyzed.

The phase transitions, magnetocaloric effect and magnetoresistance in Ni43Mn46-xCoxSn11 (x=0–5) ferromagnetic shape memory alloys were investigated. With the increase of Co concentration, the temperatures of martensitic transformation and magnetic transition in austenitic phase increase rapidly, while the magnetic transition temperature in martensitic phase shows a small decrease. In Ni43Mn41Co5Sn11, a giant magnetic entropy change of 19.1 J/(kgK) in the magnetic field of 10 kOe at 294 K, as well as a large magnetoresistance of -59% for the field change of 50 kOe at 281 K, is observed. These interesting phenomena are associated with the sudden changes of magnetization and resistance near the martensitic transition temperature. These results make the low-cost Ni–Mn–Co–Sn have promising application in magnetic refrigeration and magnetic sensor.