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991.
大柳塔煤矿五盘区5-2煤层在三维地震资料解释中发现存在一条影响较大、伸展较远的断层(DDF2断层)横切5-2煤层。综合研究表明,DDF2断层为走向为东南—西北方向(111°~291°)、倾向为西南方向(201°)的高角度正断层。该断层为坳陷盆地形成后控制部分煤层沉积:在D306钻孔和D307钻孔所在区域形成时间较早,形成于5-2煤层沉积之后,结束于4-3煤层形成之后,控制5-2煤与4-3煤之间的地层沉积,为同沉积断层;该断层在D304钻孔和D305钻孔所在区域形成时间较晚,形成于4-2煤层沉积之后,结束于3-1煤层形成之后,局部控制4-2煤层与3-1煤层之间沉积,为准同生沉积断层。DDF2断层形成于东南方向,逐渐向西北方向迁移、加剧到最后尖灭。 相似文献
992.
993.
Dr. Dandan Li Qianqian Guo Liming Ding Wei Zhang Lu Cheng Yanqiu Wang Dr. Zhuobin Xu Dr. Huihui Wang Prof. Lizeng Gao 《Chembiochem : a European journal of chemical biology》2020,21(18):2620-2627
Peroxidase-mimicking nanozymes that can generate toxic hydroxyl radicals (.OH) hold great promise as antibacterial alternatives. However, most of them display optimal performance under strongly acidic conditions (pH 3–4), and are thus not feasible for many medical uses, including burn infections with a wound pH close to neutral. Herein, we report a copper-based nanozyme (CuCo2S4) that exhibits intrinsic peroxidase-like activity and can convert H2O2 into .OH at neutral pH. In particular, bimetallic CuCo2S4 nanoparticles (NPs) exhibited enhanced peroxidase-like activity and antibacterial capacity, superior to that of the corresponding monometallic CuS and CoS NPs. The CuCo2S4 nanozymes possessed excellent ability to kill various bacteria, including methicillin-resistant Staphylococcus aureus (MRSA). Furthermore, this CuCo2S4 nanozymes could effectively disrupt MRSA biofilms in vitro and accelerate MRSA-infected burn healing in vivo. This work provides a new peroxidase mimic to combat bacteria in neutral pH milieu and this CuCo2S4 nanozyme could be a promising antibacterial agent for the treatment of burn infections. 相似文献
994.
Yunhao Fan Bo Feng Liangliang Yang Yue Zhang 《International Journal of Applied Ceramic Technology》2020,17(1):217-226
Geometries of ceramic parts for high-temperature sealing have great influence on their compression-resilience behaviors. In this work, an accurate and large-scale artificial neural network (ANN) was established to match the relationship between structural parameters and mechanical properties of ZrO2 parts fabricated by 3D printing. Four geometry parameters of the designed ZrO2 parts were imported as input and apparent Young's modulus and maximum deformation simulated by finite element method (FEM) were imported as output. FEM calculation provided 400 groups of data for the training of ANN, which greatly improved the predicted accuracy of the network. The predicted results show the mechanical performance of the parts with a range of modulus from 9.24 × 10−3 GPa to 100.35 × 10−3 GPa and a range of maximum deformation from 2.32% to 5.80% can be forecasted with error less than 8%. Based on the optimized structural parameters, the designed ZrO2 parts were fabricated by Direct Ink Writing (DIW) technique. The experimental compression-rebound property is comparable to that of ANN prediction. It demonstrates that the combined method of ANN and FEM is a preferable way to optimize the structure and guide the fabrication of complex ceramic parts by 3D printing method. 相似文献
995.
Jianhao Liu Zhou Hu Yuxia Zhang 《International Journal of Applied Ceramic Technology》2020,17(3):886-892
Dynamic indirect tension experiments were performed on zirconium diboride-silicon carbide (ZrB2−20%SiC) ceramic. Flattened Brazilian disc specimens of ZrB2−20%SiC were prepared to conduct dynamic tensile tests using the modified Split Hopkinson pressure bar system. The tensile experiments were completed at the range of loading rates from 7.53 to 74.71 GP s−1. The tensile experimental results revealed that the zirconium diboride-silicon carbide ceramic composite is rate-sensitive in terms of the tensile strength and failure mode. The dynamic tensile strength increases linearly with the loading rate and changes from 195 MPa at 7.53 GP s−1 to 654 MPa at 74.71 GP s−1. Moreover, the dynamic tensile strength decreases with the increase in critical fracture time, which conforms to Tuler and Butcher's fracture criterion. In dynamic experiments, a high-speed camera was used to examine the tensile failure process, and fragments were collected to analyze the dynamic tensile failure mechanism. The tensile fracture mode of ZrB2−20%SiC obviously showed the sensitivity of the loading rate. The fragment size of ZrB2−20%SiC ceramic decreased but the quantity of fragments increased as the loading rate increased. 相似文献
996.
Zhang Shaoliang Qu Fengjuan Wang Xueshan Xiao Ziliang Hao Xinhua Wang Li 《Nutrient Cycling in Agroecosystems》2020,116(3):345-364
Nutrient Cycling in Agroecosystems - Freeze-thaw-cycles (FTCs) change the dynamics of soil physiochemical and biological processes, and could change the soil nitrogen (N) heterogeneity in sloping... 相似文献
997.
Jiahui Yuan Gongye Zhang Xiaomei Li Qiujuan Ma Weipeng Cheng Weiwei Wang Bing Zhang Tianhui Hu Gang Song 《International journal of molecular sciences》2020,21(23)
Ubiquitin-specific protease 39 (USP39), a member of the deubiquitinating enzyme family, has been reported to participate in cytokinesis and metastasis. Previous studies determined that USP39 functions as an oncogenic factor in various types of cancer. Here, we reported that USP39 is frequently overexpressed in human lung cancer tissues and non-small-cell lung cancer (NSCLC) cell lines. USP39 knockdown inhibited the proliferation and colony formation of A549 and HCC827 cells and decreased tumorigenic potential in nude mice. Specifically, knocking down USP39 resulted in cell cycle arrest at G2/M and subsequent apoptosis through the activation of the p53 pathway, including upregulation of p21, cleaved-cas3, cleaved-cas9 and downregulation of CDC2 and CycinB1. Moreover, USP39 knockdown significantly inhibited migration and invasion of A549 and HCC827 cells, also via activation of the p53 pathway, and downregulation of MMP2 and MMP9. Importantly, we verified these results in metastasis models in vivo. Collectively, these results not only establish that USP39 functions as an oncogene in lung cancer, but reveal that USP39 has an essential role in regulating cell proliferation and metastasis via activation of the p53 pathway. 相似文献
998.
使用扫描电镜及能谱分析、化学分析方法,全面分析了使用硝盐浴进行分级淬火和等温淬火时,淬火硝盐劣化产物。结果表明:硝盐反应生成物(Na2CO3、NaOH),设备(主要是盐槽、盐泵、管道)、夹具、料盘及工件等氧化产物(FeO·Fe2O3·Fe3O4),外来物(灰尘,炭黑)是造成硝盐劣化的主要原因。据此,提出了预防淬火硝盐劣化措施:选用品质好的基盐;选用热稳定性较高的混合盐;保持淬火盐浴温度均匀,淬火前后温升可控,尽量避免“瞬间”过热使用;尽量避免外来杂质进入;做好日常维护。并简要介绍了淬火硝盐再生处理方法。 相似文献
999.
1000.
Metal Science and Heat Treatment - Features of the development of digital twins of thermomechanical steel treatment processes and examples of production tasks solved with their use are considered.... 相似文献