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In order to explore the evolution of coal cracks during nitrogen injection, the resistivity response tests of coal during nitrogen injection were carried out. The research shows that during the nitrogen injection process, the resistivity of the coal remains basically unchanged at first, then increases slowly, and increases suddenly and stabilizes at about 1.2 finally. The nitrogen adsorption of coal leads to a decrease in resistivity, and the higher the nitrogen pressure is, the greater the decrease in resistivity will be. The development of fissures in the coal will affect the conduction channel, resulting in an increase in resistivity. In the process of nitrogen injection, the resistivity change of the loaded coal is the result of the combined effect of the nitrogen adsorption of coal and the expansion of the fissures of the coal.

High temperature nitrogen, injection into coal seams is supposed to improve the per?meability and thus maintain the safety of underground mining. A novel triaxial appa?ratus is recently developed, aiming at providing the effective method to evaluate the effect of high temperature nitrogen injection. The main feature of this novel appara?tus is its high confining pressure, gas injection with high pressure as well as the high temperature. This new device can be either used for natural coal samples (e.g. intact or fractured) or the synthetic coal samples. A series of leakage tests were conducted to verify the feasibility of this instrument, the results of which have confirmed that the maximum pressure (i.e. 10 MPa) can be reached. In addition, the high temperature and pressure of nitrogen gas can also be sustain at the requested level. Based on the preliminary tests on the instrument, a large amount of tests were carried out to eval?uate the effect of nitrogen injection in enhancing the permeability of coking coal from the Pingdingshan coalfield, China, and the influence of high temperature nitrogen injection on mechanical parameters of coal was obtained.

Objective To investigate the effect of 1,8-cineol on caspase 3 expression and NO production induced by Aβ25-35 in PC12 cells. Methods PC12 cells were cultured in vitro, and cell injury was induced by Aβ25-35 with a concentration of 20 μM. 1,8-cineol (1, 3, 10 μM) was pretreated before Aβ25-35 treatment. PC12 cell viability was evaluated by MTT detection assay. Caspase 3 protein expression was detected by Western blotting. The level of NO production in PC12 cells was measured using ELISA detection assay kit. Results In cultured PC12 cells in vitro, MTT results showed that 20 μM of Aβ25-35 reduced cell viability significantly compared with control group. The cell viability was increased by pretreatment with 1,8-cineol with concentrations of 3 and 10 μM compared with Aβ25-35 only group. Western blotting results showed compared with control group, caspase 3 expression was increased significantly in 20 μM Aβ25-35 group. Compared with Aβ25-35 group, 1,8-cineol of 3 and 10 μM group reduced caspase 3 protein expression significantly. The level of NO production in PC12 cells was increased significantly, which was decreased by pretreatment with 3 and 10 μM of 1,8-cineol. Conclusions: Our results revealed a protective effect of 1,8-cineol on Aβ25-35 induced PC12 cell injury through inhibition of caspase 3 expression and NO production.

Background NUDT21 belongs to NUDT families, which is thought to play an essential role in cancer growth and progression in recent years. Abnormal NUDT21 expression is closely related to lung adenocarcinoma (LUAD). However, the expression level, gene regulation network, and prognostic value of NUDT21 in LUAD remain unclear. Besides, the active compounds of Pinellia ternata against LUAD are still not clear yet. Therefore, an in-depth study of the expression and gene regulation network of NUDT21 is of great theoretical significance and clinical demand for discovering new targets and strategies for the treatment of LUAD and the further improvement of the therapeutic effect of LUAD. Also, the targeted NUDT21 active ingredients of Pinellia ternata were sought to provide a theoretical basis for its clinical application in the treatment of LUAD. Methods A variety of online analysis tools were used in this study, including cBioPortal, ONCOMINE, GeneMANIA, GEPIA, Metascape, UALCAN, LinkedOmics, Metascape, TIMER, TRRUST, The Human Protein Atlas, TCMSP, and AutoDock Vina. Results The levels of transcription and expression of NUDT21 were significantly increased in patients with LUAD. Gene altered of NUDT21 was up to 12% in LUAD patients. However, the promoter methylation level of NUDT21 in LUAD was lower compared to normal human. LUAD patients' survival with the low expression level of NUDT21 was better prognostic value than LUAD patients with high expression level. Forty-eight nodes and 572 edges were found in the PPI network constructed with NUDT21 and its neighboring genes. Regulatory region DNA binding, transcription regulatory region DNA binding, and regulatory region nucleic acid binding were the primary function of NUDT21 and its neighboring genes. The KEGG pathway of NUDT21 and its neighboring genes were mainly involved in the apelin signaling pathway, PI3K-Akt signaling pathway, and axon guidance. Our results showed that DNMT1, HDAC1, and MYC were the critical transcription factor targets involved in the network of NUDT21 and its neighboring genes. We also found that CDK1, ATM and PLK1 were main kinase targets in the NUDT21 kinase-target network. The NUDT21 miRNA-target network was associated with MIR-302C, MIR-9, and MIR-330. Moreover, the expression of NUDT21 was positively related to the infiltration of CD8 + T cells, macrophages, neutrophils and dendritic cell. 13 active compounds of Pinellia ternata were retrieved from the TCMSP. Among them, baicalein was the best combination with NUDT21. Conclusions Our results revealed the expression and potential regulatory network of NUDT21 in LUAD, laying a foundation for further research on the role of NUDT21 in cancer. Furthermore, we offer new therapeutic targets and prognostic biomarkers for the reference. Finally, we provide potential therapeutic drugs from traditional Chinese medicine in the treatment of LUAD.

Background: Inflammation and oxidation stress are key factors in the mechanism of acute lung injury (ALI). Therefore, suppression of the inflammatory response and oxidative stress could be a potential strategy to treat lipopolysaccharide (LPS)-induced ALI. Ginsenoside Rd (Rd), a natural Ginseng extract, alleviates inflammation and oxidative stress in several diseases such as Alzheimer's disease and cerebral ischemia, but its effect on ALI is still unclear. Aims and Objectives: To explore the protective effect of Rd on LPS-induced ALI and explored associated mechanisms. Materials and Methods: Mice were divided into five groups: A sham-operated group, a LPS-induced ALI group, and three LPS groups pretreated with Rd doses of 20, 40, and 80 mg/kg, respectively. The pathological changes of lung, collagen deposition, pulmonary edema, inflammatory cytokine, oxidative stress and the expression levels of TLR4 and NF-κB were detected. Results: The oral administration of Rd dose dependently attenuated histopathologic changes in the lung, lung edema, pulmonary collagen deposition, protein concentration in bronchoalveolar lavage fluid (BALF), myeloperoxidase (MPO) activity, and inflammatory cell infiltration. In addition, Rd suppressed the LPS-induced inflammatory cytokines tumor necrosis factor-α, interleukin (IL)-6, and IL-1 β in BALF. The productions of oxidative stress-related enzymes (catalase, superoxide dismutase, and glutathione peroxidase) in lung tissue were significantly upregulated by Rd administration. However, malondialdehyde and pulmonary MPO activity was reduced in the Rd-pretreated groups when compared with LPS-induced ALI group. Rd treatment also dose dependently suppressed LPS-induced NF-κB activation and TLR4 expression. Conclusion: Overall, these findings provide evidence that Rd pretreatment inhibits LPS-induced ALI through anti-inflammatory and antioxidative actions, suggesting that it could be a promising protective drug for LPS-induced ALI.

Boron nitride materials have some excellent features, such as high temperature resistance, chemical resistance, good electric performance and radiation resistance . Along with the development of science and technology, boron nitride materials are made into coating widely, put it in the surface of metallic materials or non-metallic materials, can extend their service life significantly[1]. Atomic force microscope (AFM) is widely used for nanoscale morphology characterization and submicron scale structure material, simple sample preparation is its advantage. [2] Based on the domestic boron nitride coating as the research background, using AFM simulate the surface nanostructures of three dimensional, and evaluate the flatness of boron nitride ceramic coating which made by plasma spraying method and chemical vapor phase precipitation method respectively. The results show that the coating prepared with plasma spraying is more dense, surface flatness is smaller, surface roughness uniformity is better.

The thermal stability of aluminum titanate (AT) ceramics is the main problem that restricted its extensive applications in many fields. In this paper, AT ceramics doped with single or composite additives of MgO, SiO2, mullite were fabricated by solid phase synthesis method. The thermal stability was tested by heated for 50h at 1100°C, and the phases of the samples were tested by X-ray diffraction (XRD) , and the microstructure were tested by SEM. The mechanism of the thermal stability of AT with additive was discussed based on DSC/TGA and electron back scatter diffraction pattern (EBSP). The results show that the adding of composite additives can improve the thermal stability of AT ceramics.

This paper use zeta potential test and dynamic viscosity test to research the influence of different factors such as pH value, mass fraction of solid phase and dispersant content on the liquidity of Al2O3 slurry. The test results show that, when the solid-phase mass fraction and particle size are given, the absolute value of zeta potential increases with the rise of pH value, raise at first then descrease with the adding of (NaPO3)6. This article analyzes the phenomena from a legal point of electric double layer effect. The results of liquidity test are consistent with zeta potential test. The optimum value of pH value, mass fraction of solid-phase and dispersant content are determined by formulation design. The study develop a Al2O3 slurry with high fluidity which has an important significant in slip casting process of Al2O3 ceramics.

In recent years, as a new form of public transport, the modern tram has been the rapidly developed and widely applicated at home and abroad. In order to ensure the safe operation of the modern tram, the groove rail damage block is used to explore suitable method of flaw detection. To solve the problem, finite element software was used to model the modern tramway structure, internal groove rail stress changes was analysised, the appropriate internal damage distribution was determined, combined with the corresponding national standard, a new groove rail damage test block was put forward, to determine the appropriate modern tram methods of flaw detection provide detection standard.

Aim The current standard treatment for IgA nephropathy relies on steroid and/or immunosuppressive therapy and angiotensin converting enzyme inhibitors (ACEI) or angiotensin receptor blocker (ARB). This study examines the benefits and safety of combining valsartan with clopidogrel and leflunomide as a treatment for progressive IgA nephropathy. Methods Patients with primary IgA nephropathy, confirmed by renal biopsy, were recruited for this study. Patients were separated into four groups (n = 42 each) after 2 months of run-in period of valsartan treatment. All patients were treated with valsartan alone (Group 1) or valsartan and either clopidogrel (Group 2) or leflunomide (Group 3) or both clopidogrel and leflunomide (Group 4). Each group was followed up for their next 24 months for 24 h urinary protein excretion, serum creatinine and estimated glomerular filtration rate (eGFR) to assess the effect of the treatment. Adverse effects were recorded concurrently to evaluate the safety of the treatment. Results Of all 168 patients, 107 were males and 61 were females, with an average age of 33.8 ± 8.79 years. Baseline characteristics were comparable among the four groups (P > 0.05) prior to the experimental treatment. There was a significant (P

This paper studied the problems met in the quantitative analysis of synthetic Mullite phase,which was based on the analysis of various typical Mullite composite scheme. A method of quantitative analysis of Mullite phase (excluding amorphous phase SiO2) by use X-ray diffraction was discussed. The error of the analysis can be verified by chemical analysis of Al2O3 content. The method can effectively improve the accuracy of quantitative analysis of the Mullite phase, the error analysis is less than 3%. The error range can meet the accuracy requirement of Mullite content in the production.Studies show that this method is preliminarily solved how to quantitative the content of mullite phase by X-ray diffraction method .

This paper proposes an information hiding method based on word text, according to the theory of the human eye cones for the color sensitivity; the human eye is least sensitive to blue. I change the lowest two bits of G component in the carrier text character RGB color value, change the lowest two bits of R component in the carrier text character RGB color value, and change the lowest four bits of B component in the carrier text character RGB color value, So that each carrier text character can hide 8 bits binary information. RGB color value of character underline can hide 24 bits information; the combination of these two methods can hide 32 bits binary information. After testing, the results show that the algorithm hiding rate is high, the algorithm is stable and easy to implement, has a certain application value.

Fused Quartz crucible with large scale was formed by gelcasting processing in this paper. Effects of dispersant, pH values and particle grading on solids content of slurries were discussed to increase the volume density of the green compacts and decrease the shrinkage and deformation during sintering. Effects of acrylamide content and the ratio of acrylamide to coupling agent on bending strength of the green compacts were investigated. Effects of the amount of initiator and curing temperature on the gelcasting processing were studied as well. The green compacts with solids content of 80% was obtained when the addition ratio of dispersant to Quartz powders was 0.3wt %, the ratio of Quartz powders in D50 of 1.9μm and 7.6μm was adjusted to 3:7, the addition ratio of acrylamide to Quartz powders was 1.0wt % and the ratio of acrylamide to coupling agent was 16:1. The bending strength of the sinterred produts was found to be 76.0MPa with volume density of 1.94 g/cm2. Fused Quartz crucible prepared under conditions mentioned above was 800mm in length, 800mm in width and 400mm in height.

Electrospinning is an effective appoach to get one-dimensional nano structured materials.Thin PVA/zirconium oxychloride and yttrium nitrate composite fibers were prepared by using precurssor solution and electrospinning technique. Influence factors in PVA content and concentration of inorganic salts on nanofibers were discussed in this paper.After calcinations of the above precursor fibres, ZrO2 nanofibres could be successfully obtained.The fibres were characterized by SEM, XRD, respectively.

The effects of P25 TiO2 made by DEGUSSA and one kind nano-titanium dioxide made by a certain company in China (Expressed by Tc) on Escherichia coli were tested by the minimal inhibitory concentration (MIC) method, and the status dispersed of two kinds nano-TiO2 and the micro-phenomenon of the effect on Escherichia coli were observed by scanning electron microscope (SEM). The hydroxyl radical (•OH) signal intensity in liquid produced by nano-TiO2 was tested by electron spinning resonance (ESR). It was found that the MIC of the P25 and Tc were 500 mg/L and 5 g/L, respectively. The cells of E. coli which were attached by the nano-TiO2 particles were damaged strongly, and the membrane was dissolved and dispersed under SEM. The intensity of •OH signal produced by P25 was stronger than that of Tc tested by ESR. The size of E. coli was 0.4~0.7×1~3 µm, and the average diameter of nano-TiO2 was 20 nm. When the nano-TiO2 particles touch the E. coli, it would stick to the surface of the cell wall and destroy the cell membrane, lead to the canker of cell membrane and the outflow of cytoplasm. The difference of the MIC between the two kinds of nano-powders may be due to their dispersion degree and the particle diameter which influence the •OH production.

The types and characteristics of phase change materials were discussed. With respect to application in building materials, the PCM should have more attractive properties including high latent heat values, stability and proper melting point, inflammability, corrosiveness and supercooling. Phase change building material (PCBM) was prepared using vacuum absorption method and tested by means of Differential Scanning Calorimetry(DSC) and Scanning Electron Microscopy(SEM). The testing results have shown that organic PCM was absorbed into the holes of inorganic carriers completely and distributed evenly with stable performances. It is concluded that the composite PCM has steady temperature-adjusting function and the preparation means is acceptable.

TiO2 was supported on crude sepiolite by boiling reflux method. According to the X-ray diffraction, TiO2 is rutile-anatase mixing type while the composite prepared by the same method is rutile crystal. Scanning electron microscope study shows that TiO2 balls grow onto fibrous sepiolite like strings of grapes. The binding energy of Ti2p becomes 0.2eV lower in the composite. The photocatalytic performances are evaluated through studying the ability of generating hydroxyl radical（•OH）by electron spin resonance(ESR), and the decomposition rate of methyl orange in aqueous solution. It is found that the quantity of hydroxyl radical increases and the photocatalytic activity is enhanced for TiO2/sepiolite composite under natural light.