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Objective Since the collision and compression of the Indo-European continental plates, the Qinghai-Tibetan Plateau has experienced uplift and intra-land deformationSince the collision and compression of the Indo-European continental plates, the Qinghai-Tibetan Plateau has experienced uplift and intra-land deformation. Similarly, the Sichuan-Yunnan block underwent lateral escape and rotationSince the collision and compression of the Indo-European continental plates, the Qinghai-Tibetan Plateau has experienced uplift and intra-land deformation. Similarly, the Sichuan-Yunnan block underwent lateral escape and rotation. Although extensive paleomagnetic studies have been conducted on the rotation of the central and western parts of the Sichuan-Yunnan rhombic block, less attention has been paid to the rotation of its eastern partSince the collision and compression of the Indo-European continental plates, the Qinghai-Tibetan Plateau has experienced uplift and intra-land deformation. Similarly, the Sichuan-Yunnan block underwent lateral escape and rotation. Although extensive paleomagnetic studies have been conducted on the rotation of the central and western parts of the Sichuan-Yunnan rhombic block, less attention has been paid to the rotation of its eastern part. This study employs fluvial geomorphology, which is highly sensitive to mass rotation, to investigate the rotation and uplift in the Laoyingshan region, situated in the eastern part of the Sichuan-Yunnan block. Methods A 30 m resolution digital elevation model (DEM) was used to identify and analyze 22 basins in the study area. Four geomorphological parameters were examined: local topographic relief ratio, longitudinal profile, normalized steepness index, and basin azimuth. Results (1) According to regional topographic relief, the low-relief area in the Laoyingshan region is mainly located near the Sijia River and the Baizai River on the western side, whereas the high-relief area is mainly found near the Dabai River and the Gongshan River on the eastern side of the Laoyingshan. The relief around the Dabai and Gongshan Rivers was greater than that around the Sijia River on the western side of Laoyingshan. (2) The normalized steepness index in the Laoyingshan area gradually decreased from north to south. The high-value areas are primarily located near Awang and Jinyuan, corresponding to the east and west branches of the Xiaojiang Fault. In contrast, the low-value areas were mainly distributed at the top of the Laoyingshan and south of the Baozai River in the study area. (3) The results of the river longitudinal profile indicated that the average surface uplift of the area was approximately 358 m. (4) Based on the results of the watershed azimuth angle, the Laoyingshan area underwent a counterclockwise rotation of approximately 15°. Conclusion The analysis suggests that since the Late Miocene, the western region of the Sichuan-Yunnan block, located west of the Yuanmou Fault, has experienced fewer effects from strike-slip faults and has predominantly undergone clockwise rotation. Conversely, the eastern region of the Sichuan-Yunnan block, influenced by strike-slip faults, underwent counterclockwise rotation with differential uplift. [ Significance] The fluvial geomorphological index outlines the tectonic rotation of the eastern Sichuan-Yunnan block.

Here we reported two new triazole-based coordination polymers (CPs), i.e., [Zn(Hdatrz)(μ 2-O)]n (1) together with [Mn(Hdatrz)(C2O4)]n·n(H2O) (2) (Hdatrz = 3,5-diamino-1,2,4-triazole), which were generated under solvothermal conditions. The influence of different metal ions on the structure and properties of CPs was investigated. The CPs’ whole structures have been completely characterized by the powder X-ray diffraction, Fourier transform infrared spectroscopy, and thermogravimetric analysis. It is noteworthy that, upon excitation at 390 nm, ligands of compounds 1 and 2, as well as the metal complexes, all exhibit luminescence at 432 nm.

In situ disulfide bond formation affords a new flexible dicarboxylic acid ligand of 3,3′-dithiobisbenzoic acid (3,3′-H2DTBA), which assembled with Co(ii) ions under hydrothermal conditions, generating a novel metal–organic framework (MOF), namely, [Co(3,3′-DTBA)2(H2O)2]n (1). This compound is assembled from layered structures, featuring weak interlayer interactions that can reduce pore blockage through relative sliding. The results of photocatalytic experiment indicate that MOF 1 is a good semiconducting material and it can function as photocatalyst for degrading methylene blue under the ultraviolet light irradiation. Cyclic experiments demonstrated its good stability and long-lasting photocatalytic performance, indicating its potential application value.

A novel Cd(II) compound, namely [Cd6(TCA)4(4-bpmh)(DMA)2(H2O)2]n·4n(H2O) (denoted as 1, H3TCA = 4,4′,4″-tricarboxytriphenylamine, 4-bpmh = N,N-bis(pyridin-4-ylmethylene)hydrazine, and DMA = N,N′-dimethylacetamine), has been solvothermally prepared via a dual-ligand strategy that employs two organic ligands to fulfill different functions. The solid of compound 1 shows blue luminescence at room temperature.

With the continuous application and popularization of distributed energy, DC power distribution will become the mainstream form of future power distribution system. As a new type of power distribution system, the overvoltage and insulation coordination of flexible DC power distribution urgently needs further research and improvement. The addition of medium-voltage DC circuit breakers has also led to fundamental changes in the operating overvoltage transient characteristics of the system. It is necessary to analyze the operating overvoltage distribution characteristics and insulation coordination of the flexible DC distribution network with DC circuit breakers. Firstly, the electromagnetic transient simulation model of ±10 kV ring-network flexible DC power distribution network is constructed, and the protection action scheme based on DC circuit breaker is designed. Then, the ±10 kV ring network flexible DC power distribution system is simulated and analyzed for operating overvoltage, horizontal spatial distribution characteristics of its amplitude and the decisive working condition of the maximum overvoltage at key positions are obtained, insulation coordination scheme of the ±10 kV ring network flexible DC power distribution system is proposed. Finally, the simulation analysis of the transient induced overvoltage of the DC cable sheath under the influence of the action of the DC circuit breaker is carried out. The results show that the addition of DC circuit breakers improves the reliability and flexibility of DC distribution network, and the layout of arrester and cable metal shield protector is further optimized, which is of great significance to the design of insulation matching scheme of flexible direct distribution network of ring network.

The SiC coating prepared on graphite substrate can effectively solve the corrosion and powder loss problems of graphite material in environments with high temperature and corrosive gas. In this paper, a SiC coating was prepared on the surface of graphite substrate. The deposition process parameters were adjusted and optimized to realize rapid manufacturing of high - performance SiC coating with the aim of providing theoretical basis and technical support for SiC coating’ application on the surface of graphite substrate. An industrial - grade chemical vapor deposition equipment was employed to prepare the silicon carbide coating on the surface of graphite substrates using methyl trichlorosilane (MTS) and H2 as raw materials. The effects of furnace pressure and sample position on the microstructure and thermal fatigue resistance of the coating were studied by analysis and testing methods such as scanning electron microscopy, X - ray diffractometer and vacuum thermal cycling. Results showed that when the furnace pressure was 2.0 kPa, a high - purity silicon carbide coating with single grain growth orientation could be prepared. As the furnace pressure increased, the deposition rate and thermal fatigue resistance of the coating both showed a non - monotonic change of first rising, then falling and then rising again. When the furnace pressure was 2.0 kPa, the silicon carbide coating had the highest deposition rate and the best thermal fatigue resistance. The coatings prepared with different sample positions were all pure SiC coatings, and the closer the substrate suspension position to the air distribution plate, the faster the coating deposition rate was and the better thermal fatigue resistance the coating showed. When the furnace pressure was 2.0 kPa and the sample position was 300 mm, a SiC coating with good thermal fatigue resistance could be quickly prepared.

The access of ultra high voltage (UHV) gas-insulated transmission line (GIL) affects both the transient recovery voltage (TRV) amplitude and the rate of rise of TRV (RRRV) of circuit breakers,which may endanger the breaking capacity of circuit breakers. Based on the double-circuit UHV accurate current (AC) overhead line on the same tower and the double-circuit GIL hybrid transmission line,EMTP-ATP simulation is used to study the influence of GIL length,access position and GIL lead station measurement equipment on the TRV amplitude and RRRV of the circuit breaker when a three-phase short-circuit fault occurs at the end of the circuit breaker in the substation. The simulation results show that the access of the GIL has a greater impact on the TRV amplitude and RRRV of the circuit breaker. The increase in the length of the GIL has a greater impact on the TRV amplitude,but the impact on RRRV is small. In order to limit the RRRV,the GIL should be installed in the middle of the overhead line,and the metal oxide varistor (MOV) should be installed to limit the TRV amplitude. The measurement equipment of the GIL terminal station has little effect on the TRV amplitude and RRRV of the circuit breaker. The research results can provide a reference for the TRV calculation and parameter design of circuit breakers in UHV lines with GIL.

Reported here is a new Cu(ii) compound with the formula of {Cu4(μ 2-Cl)6(μ 4-O)(4-NH2-py)4}n (1, 4-NH2-py = 4-amino-pyridine). The analysis of X-ray diffraction shows that the complex 1 indicates a 0D separated skeleton with {Cu4(μ 2-Cl)6(μ 4-O)} tetranuclear cluster. The interactions of H-bond between the amino groups and μ 2-Cl anions from adjacent 0D cluster further extended this 0D cluster into a 3D supramolecular framework. In addition, this compound has excellent photocatalytic activities for the degradation of methyl blue under UV radiation. The cyclic testing results indicate that complex 1 exhibits good recyclability, as it can be repeated for as many as five cycles with no noticeable loss of performance, revealing its potential application in pollutant degradation within the environmental field.

Intrahepatic cholangiocarcinoma (ICC) is one of the most common malignant liver tumors afterhepatocellular carcinoma, the incidence rate of which in our country is rather high. At present, surgical resection isstill main treatment for ICC. However, due to the lack of specific symptoms at early stage, ICC patients are oftendiagnosed at late stage and loss of the opportunity of surgical treatments. Conversion therapy is a novel conceptproposed recently. It demonstrated that malignant tumors that cannot be resected initially can be downsized by various treatments, so that patients obtained the chance of surgical treatments and get prolonged survival time. Withthe development of novel anti-tumor drugs, conversion therapy of ICC also is in the first flush of dawn. This review summarizes the current situation of ICC conversion therapy and our practical experience.

In view of problems of many steps, low automation degree and more human interference factors in current measuring process of drilling cuttings gas desorption index Δh2 under different gas adsorption pressure conditions in laboratory, a high precision automatic measurement system for coal drill cuttings gas desorption index Δh2 based on single-chip microcomputer was designed. The system takes Atmega16 single-chip microcomputer as the core, and takes USART_HMI touch screen as input and output devices of system instructions. The single-chip microcomputer is used to operate various sensors, relays and solenoid valves to complete process of automatic degassing, adsorption, pressure relief and determination of coal samples through identifying touch screen instructions, so as to obtain final measured coal drill cuttings adsorption pressure desorption index Δh2 under different adsorption pressure conditions. The test results show that the relative error of the automatic measurement system is controlled within 5% compared with the existing coal drill cuttings gas desorption instrument,which has good practicability and data accuracy.

C19H19NO6, triclinic, P1̅ (no. 2), a = 7.009(3) Å, b = 8.081(3) Å, c = 15.218(8) Å, α = 101.973(9)°, β = 99.137(10)°, γ = 102.164(7)°, V = 805.5(6) Å3, Z = 2, Rgt(F) = 0.0520, wRref(F2) = 0.1271, T = 296(2) K.