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In order to prevent accident cases and improve safety in the mining industry, a safety risk assessment and management process is needed to identify and respond to high-risk hazards in mines. This study aims to investigate the main safety risks factors influencing the typology of accidents in the Panzhihua OP-UG iron ore mine with the concept of minimizing them, reducing injuries and fatalities, and improving prevention policies. A methodology based on the analytic hierarchy process and fuzzy comprehensive evaluation (AHP-FCE) is applied to conduct a study on the assessment and evaluation of mine safety risks. Upon investigating the safety situation at the mine site, 85 risk factors were identified, of which 49 factors were considered to be non-threatening and therefore compatible with existing control measures. The remaining potential hazards, altogether 36 factors, were ultimately categorized into six major specific groups. A mine safety index system and safety risk evaluation model are established to support the evaluation process. The results show that the overall risk level of the Panzhihua OP-UG iron mine is at a medium level with a score of 86.5%. Appropriate risk management measures were recommended for each risk factor from the perspectives of theoretical analysis, safety system optimization of mine technology, disaster prevention and control of slope failure, etc. Finally, this research serves as a great industrial value and academic significance to provide technical support for the safety production of mining enterprises. Hence, the FCE method can serve as a technique to accurately evaluate the impact of iron mine risk.

Here, we report the photocatalytic synthesis of N2/H2O to NH3 over plasmonic metal Pt supported on the coal-based graphene oxide/silica dioxide. Through the capture experiments of active substance, the photoinduced electrons were found to play a key role during the photocatalysis. As proving by the FDTD theoretical calculation, the photogenerated electric filed can distribute around the surface of Pt nanoparticle via SPR effect under visible light, which can weaken the bond of N≡N by polarization. NH3 and N2H4 were found to be the photocatalytic products due to the results of the 1H NMR characterization.

Jie Chen,1,2,* Chengxian Ma,2,* Yufeng Zhang,2 Shuai Pei,1,2 Mingyu Du,2 Yujie Zhang,2 Luxi Qian,2 Jianlin Wang,2 Li Yin,2 Xia He1,2 1Xuzhou Medical University, Xuzhou, Jiangsu, People’s Republic of China; 2Jiangsu Cancer Hospital, Jiangsu Institute of Cancer Research, Nanjing Medical University Affiliated Cancer Hospital, Nanjing, Jiangsu, People’s Republic of China*These authors contributed equally to this workCorrespondence: Xia HeXuzhou Medical University, Xuzhou, Jiangsu, People’s Republic of ChinaEmail hexiabm@163.com Li YinJiangsu Cancer Hospital, Jiangsu Institute of Cancer Research, Nanjing Medical University Affiliated Cancer Hospital, Nanjing, Jiangsu, People’s Republic of ChinaEmail yinli_2012@126.comBackground: Mounting evidence has reported that microRNA-154-5p (miR-154-5p) is involved in the development of multiple cancers, but its function in nasopharyngeal carcinoma (NPC) remains not well investigated.Methods: Real-time quantitative PCR (qRT-PCR) was used to detect miR-154-5p expression in NPC tissues and cells. CCK8, colony formation, wound healing and transwell assays were performed to assess cell proliferation, migration and invasion. Dual-luciferase reporter assays and Western blots were performed to confirm the target gene of miR-154-5p. Rescue experiments were conducted to explore the influence of target gene KIF14 on the functions of miR-154-5p. Xenograft tumor model was conducted to detect the effect of miR-154-5p in vivo.Results: qRT-PCR results revealed that the expression of miR-154-5p was down-regulated in NPC tissues and cell lines compared to normal nasopharyngeal tissues and cell line. Overexpression of miR-154-5p inhibited cell migration and invasion. However, miR-154-5p had no influence on the proliferation of NPC cells. MiR-154-5p overexpression suppressed xenograft tumor metastasis in vivo. Dual-luciferase reporter analysis identified KIF14 as a target gene of miR-154-5p. Rescue experiments showed that knockdown of KIF14 reversed the effect of inhibiting miR-154-5p expression on NPC cell migration and invasion.Conclusion: Taken together, miR-154-5p suppresses tumor migration and invasion by targeting KIF14 in NPC. The newly identified miR-154-5p/KIF14 interaction offers further insights into the progression of NPC, which may represent a novel target for NPC diagnosis and treatment.Keywords: MiR-154-5p, KIF14, nasopharyngeal carcinoma, migration and invasion

In this paper, petroleum pitch-based GO was obtained by using petroleum pitch as carbon source, and Ni&NiO was prepared by reducing of NiSO4·6H2O. Then, Ni&NiO/GO was prepared by in situ loading Ni...

Petroleum pitch-based graphene oxide (GO) was prepared by using petroleum pitch as carbon source, and GO/WO3 composite catalyst was prepared by hydrothermal synthesis. At the same time, the performance of GO/WO3 photocatalytic reduction of CO2 to produce renewable hydrocarbon fuel was studied. The results showed that the introduction of GO promoted the absorption of visible light, enhanced the adsorption performance of CO2 in the catalyst surface, improved the separation efficiency of photogenerated electron hole pairs and made the protons produced by water decomposition more involved in the reduction reaction of CO2, thus greatly enhancing the efficiency of CO produced by Photocatalytic reduction of CO2. The yields of CO and H2 were 151.8[Formula: see text][Formula: see text]mol[Formula: see text]g[Formula: see text] cat[Formula: see text] h[Formula: see text] and 46.3[Formula: see text][Formula: see text]mol[Formula: see text]g[Formula: see text] cat[Formula: see text] h[Formula: see text], which were about three times and two times of pure WO3 under the same conditions.

Coal-based carbon nanoscrolls (CNS) were prepared through improved Hummers oxidation method using Xinjiang Wucaiwan coal as a carbon source, after removing impurities by acid treatment and graphitizing pretreatment. Then, the Cadmium sulfide (CdS) generated by the precipitation reaction of cadmium acetate and sodium sulfide was loaded on the coal-based CNS substrate in situ to prepare the composite photocatalyst CdS/CNS with different CdS content. The structure of the as-prepared CdS/CNS characterized, and the photocatalytic N2/H2O ammonia synthesis performance was studied. The results show that CNS is a kind of coal-based carbon nanomaterial evolved from graphene oxide (GO), yet it is more stable than GO and has a similar photoelectric property. Using it as a nano-catalyst substrate of the CdS can not only improve the agglomeration of CdS nanoparticles but also create structural defects in the composite catalyst that are favorable for photocatalytic reaction on the composite photocatalyst. It also provides more active sites for the photocatalytic reaction, and greatly increases the photoelectron transfer rate of the composite catalyst as well. Besides, CNS is a good catalyst carrier. The composite catalyst with CNS has a much better enhancement than pure CdS nanoparticles in both adsorption and activation of N2 and response to visible light. The 80%-CdS/CNS was used in the synthesis ammonia of photocatalysis N2/H2O. After 4 h reaction, the ammonia yield reached 1.337 mmol/L·g cat., which was about 3.29 times that of the ammonia synthesis using pure CdS under the same conditions.

Currently, low-dimensional materials are a hot spot in the field of thermoelectric research, because the thermoelectric properties will be significantly improved after the low-dimensionalization of bulk materials. In a bulk material, its thermoelectric figure of merit ZT value cannot be increased by changing a single parameter, because the parameters of the material are interrelated to each other, which is not conducive to the research of internal factors and thus limiting the efficiency of thermoelectric material, but thermoelectric material on a micro-nano scale is more flexible to adjust its thermoelectric figure of merit ZT value. There are many different kinds of methods of implementing the low-dimensionalization of bulk materials. In this paper, size-controllable Si micro/nanobelts are prepared based on semiconductor micromachining and focused ion beam (FIB) technology, and the thermoelectric properties of Si micro/nanobelts of different sizes are comprehensively studied by the micro-suspension structure method.In this experiment, we find that the conductivity of doped Si micro/nanobelt is significantly better than that of bulk Si material, that as the width of the Si micro/nanobelt decreases, the thermal conductivity of the material decreases significantly, from 148 W/(m·K) of bulk silicon to 17.75 W/(m·K) of 800 nm wide Si micro-nanobelt, that the Seebeck coefficient of the material is lower than that of the corresponding bulkmaterials. The decrease of thermal conductivity is mainly due to the boundary effect caused by the size reduction, which leads the phonon boundary scattering to increase, and thus significantly inhibiting the behavior of phonon transmission in the Si material, thereby further affecting the transmission and conversion of thermal energy in the material. At 373 K, the maximum ZT value of the 800 nm wide Si micro/nanobelt reaches ～0.056, which is about 6 times larger than that of bulk silicon. And as the width of the Si micronanobelt is further reduced, the thermoelectric figure of merit ZT value will be further improved, making Si material an effective thermoelectric material. The FIB processing technology provides a new preparation scheme for improving the thermoelectric performances of Si materials in the future, and this manufacturing technology can also be applied to the low-dimensional preparation of other materials.

Synthesis and visible-light photocatalytic N2/H2O to ammonia at atmospheric pressure and room temperature is considered to be the most ideal ammonia synthesis technology. In this study, coal-based carbon dots (CDs) were prepared by H2O2 oxidation method using cheap and ubiquitous coal as the carbon source. Then the gold sol was connected to CDs to obtain a core-shell structure photocatalyst Au@CDs by sodium borohydride (NaBH4) reduction method. While characterizing the material structure, the photocatalytic N2/H2O to ammonia performance of Au@CDs was investigated. The results show that the introduction of CDs in Au @CDs photocatalysts can not only improve the performance of the catalyst to excite carriers in visible light, but also inhibit the recombination of photogenerated electron-hole pairs, promote the charge transport ability and make photogenerated electrons and holes move smoothly to the catalyst surface. Meanwhile, the adsorption and dissociation capacity of N2 on the catalyst surface can be improved, thereby the photocatalytic N2/H2O ammonia synthesis reaction of Au@CDs can proceed smoothly.

This paper introduces a three-dimensional numerical model of simulating the tunneling cycle of tunnel-type anchorage by the large finite element software ABAQUS. With tunneling cycles, the space-time effect for footage is analyzed comparatively, which are between the tunnel in headings and tunnel in foots. There are three parameters for evaluating the construction methods, that contain vertical displacement of tunnel vault, vertical displacement of tunnel invert, and horizontal displacement of tunnel wall. The results show that all the values of the above parameters are in the control. Hence, the construction methods of the engineering are available.

Mining maximal frequent itemsets get the advantage of a relatively small number of itemsets. Compared to mining frequent itemsets and mining frequent closed itemsets, such algorithm has higher time and space efficiency. According to the features of data streams and combined sliding window, a new algorithm E-FPMFI which is based on orderly-compound policy for mining maximal frequent itemsets in data stream is proposed. The algorithm based on basic window updates information from data stream flow fragment and scans the stream only once to gain and store it in frequent itemsets list. The algorithm construct FP-tree, then compress orderly FP-tree by merging nodes which has equal minsup in same branch, also uses subset mix pruning technique, avoid superset checking. The experimental results show the algorithm has higher time, space efficiency and good scalability.

The process of constructing breakwater project is a course of dumping rockfill. And the slit is squeezed out. The simulation of dumping rockfill is mainly by Lagrange or Euler algorithm. But these two algorithms have disadvantages in the process of simulating. The course of extruding slitl is a dynamic contact process of rockfill, seawater and silt. This paper studies the basic principle of Coupled Euler Lagrange algorithms (CEL). The course of extruding slit is simulated by CEL with ABAQUS. This paper studies the course of extruding slit by dumping rockfill in the project of Haiyang harbor. The size effect of rockfill on extruding depth is put forward. The research results can be used be used for reference in other engineering.

The influence of mixed liquor suspended solids (MLSS), soluble microbial product (SMP), extracellular polymeric substance (EPS), colloidal particles and other factors contributed to membrane fouling was analyzed in this pilot test by membrane bioreactor (MBR) process for the leather printing and dyeing industrial park mixed wastewater treatment. The results showed that slight membrane fouling occurred after 120-day experiment with an observable increase in membrane resistance R20 from 1.5 x 10(12) m(-1) to 1.8 x 10(12) m(-1). Also, a linear correlation was found between the proportion of colloidal particles concentration in TOC of MBR former solution and membrane filtration resistance change. However, the change of MLSS, SMP, EPS and other factors was not correlated with the membrane filtration resistance change. Therefore, the colloidal particle was considered to be the main factor causing membrane fouling, which attached to the membrane surface and deposited to block the membrane pore.

In this paper, the concept and characters of Agent technology are researched. By applying Agent technology into Military Simulation System, a Military Simulation System framework based on Multi-Agent technology is put forward. Each Agent, model warehouse, knowledge warehouse and database of the Military Simulation System framework are researched. Finally, the communication and cooperation between Agents are discussed. Keywords-Multi-Agent; Military Simulation System; Simulation; Cooperation

Alzheimer's disease (AD) is the most ordinary kind of dementia. Identifying genes associated with AD is a new topic, and the key is to design algorithm to search AD genes. Gene order is a permutation of genes in which similar genes are ordered together. In this paper, a function is defined on gene order, and function value measures the similarity degree between a gene and its neighbors. Through the function value, the neighbors of a gene can be identified. The genes keeping as neighbor of AD gene (APOE, presenilins 1 or 2) at any stage (control, incipient, moderate, severe) are identified as the candidate of the gene associated with AD, where AD gene has been proved acting risk factor of AD. Experiment results of this paper have been proved some genes associated with AD.