bluuebunny/crossref_metadata_2025_split huggingface dataset:
Analysis of Coal Seam Gas Emission Based on Mine Gas Drainage Statistics
Authors: Zhang Jufeng , Li Xuguang , Yang Fengfeng , Xu Tai , Zheng Chao , Miao Zaiquan , Zhang Jianjiang 
Published: November 2019

Abstract
The statistics and analysis of mine gas extraction is very important for mine gas control, which provides a basis for the formulation of mine gas extraction plan. Because of its simple and convenient characteristics, it is favored by the engineering and technical personnel in the coal mine field, and has been widely used, and achieved good results. Based on the statistics of gas drainage in Weijiadi Coal Mine from 2008 to 2018, the characteristics and quantity of gas emission are analyzed according to the statistical results of gas drainage in Weijiadi Coal Mine, and the characteristics of gas emission in the process of driving in the main mining seam are predicted, and the mathematics relations of the length of driving roadway and the quantity of gas emission is obtained.
Mathematical Modelling and Simulation of Adsorptive Moving Bed Reactor for Claus Process
Authors: Zhang Yun 
Published: November 2019

Abstract
Fixed bed reactors are widely used in desulfurization processes. However, this kind of reactors has an obvious disadvantage leading to discontinuous operation that the catalysts and adsorbents must be regenerated periodically. As a continuous operated reactor, moving bed reactor can let both gas and solids move through the reactor, making it possible to remove the saturated adsorbents as well as deactivated catalysts. Meanwhile, fresh gas and solids can be fed into the reactor. This paper builds mathematical model of adsorptive moving bed reactor based on Claus Process. The model is simulated with Aspen Custom Modeler. Simulation results show that adsorptive moving bed reactor has good performance in Claus Process. Under the reaction conditions, the adsorption ability is limited by the temperature. Adequate increment of adsorbent volume fraction in the solids can improve the reactor’s performance.
Research on Analysis Method of Highway Engineering Metrology Comparison Results
Authors: Zhang Chunxia , Lin Zhidan , Peng Lu , Miao Na , Wang Yixu 
Published: November 2019

Abstract
This paper combines the needs of the measurement and traceability of the measurement standard in the highway industry, and the application of the theoretical analysis and measurement method in the highway engineering metrological verification institution through theoretical analysis. The differences and application scopes of the two commonly used statistical methods are discussed with examples. The results show that the analysis results of the two comparison methods are basically the same. In practical applications, the appropriate method should be selected according to the comparison purpose and sample characteristics.
FEM Analysis of Stress Charecteristics of Cut-off Wall in Rushan River Groundwater Reservoir
Authors: Yu Hairui , Yu Songwei , Li Chen , Li Wanglin 
Published: November 2019

Abstract
In order to evaluate the safety of stress intensity of the plastic concrete cut-off wall in Rushan River underground reservoir, the most dangerous section of the cut-off wall was selected, the stress distribution characteristics of the cut-off wall were analyzed by ABAQUS finite element analysis method, the safety strength was rechecked, and the calculation results are compared with the stress calculation results of the elastic foundation beam method. The following conclusions are drawn. The calculation results of the two methods show that the water level difference between the two sides of the cut-off wall has a great influence on the stress of the cut-off wall. The maximum compressive stress of cut-off wall is less than 3 Mpa and the maximum tensile stress is less than 0.65 Mpa, which meets the design strength of plastic concrete cut-off wall. ABAQUS finite element analysis method is feasible in the stress analysis of cut-off wall. Compared with the results of elastic foundation beam method, the finite element method can better reflect the stress distribution and displacement deformation on both sides of cut-off wall. ABAQUS finite element analysis method has certain advantages in stress analysis of cut-off wall.
Research and Application of Peat in Agriculture
Authors: Cao Shiliu 
Published: November 2019

Abstract
Peat has excellent permeability, good hydrophilicity and strong activitya and wide range of applications in agriculture, which is a loose fibrous natural biomass material, in the paper, the research and application of peat as soil amendment, fertilizer and horticulture were elaborated in detail, and the application prospect of peat in agriculture was prospected.
Impacts of High Frequency Spectral Tail of the Surface Gravity Waves on the Stokes Drift
Authors: Xu Junli , Zhao Yong 
Published: November 2019

Abstract
The impacts of different wave spectrum formulations with high frequency tail on the Stokes drift are studied in this paper. Two wave spectrum formulations are described. One is from the Donelan and Pierson spectrum extended to the high frequency range (denoted by EDP spectrum) by Paskyabi and Jenkins, and the other is a combined spectrum (termed the Combi spectrum) provided by Tsagareli. Using the EDP spectrum and Combi spectrum, the Stokes drift velocities and Stokes transports are calculated for the different wind speeds. The results show that the high frequency spectral tail of the surface gravity waves obviously changes the Stokes drift velocity on the sea surface, but has little impact on the Stokes transport.
Research on Wear Theory of L-Shaped Elbow
Authors: Yu Jin , Du Xinjie 
Published: November 2019

Abstract
Starting from general wear theory, the solid particle causes erosion loss in pipeline is studied. The motion trajectory of solid particle and theoretical wear rate equation of material surface when elbow suffers erosion wear are summarized, and the effect of attack angle and impact velocity on wear rate of L-Shaped elbow is qualitatively analyzed, so as to provide theoretical basis for the design of elbow.
Analysis of quantitative expression of viscous coefficient for sediment-laden flow
Authors: Xiao Qianlu , Feng Qing , Zheng Yanshuang 
Published: November 2019

Abstract
The modified viscous coefficient of non-uniform sediment-laden flow based on Zhu Junda's theoretical equation is generally utilized in the calculation mode of hyper-concentrated flow at present. Nevertheless, the gradation conservation of nonuniform sediment was neglected in the theoretical derivation with the irrational loss of fine sediment. The assumed replacement conditions in the derivation resulted in the coarsening effect of suspended sediment gradation in muddy water. Meanwhile, the degree of particle coarsening would be more serious with the increasing replacement times of micro-volume of sediment groups. The computed result of Zhu Junda's equation would underestimate the viscosity of sediment-laden water. Furthermore, the magnitude and velocity of deviation increment for the equation are reckoned. Compared Einstein's viscosity formula with the Taylor Series expansion of Zhu Junda's equation, the Einstein's formula with strong limitations is not a special case. In accordance with suspended sediment gradation, this paper brings in the displacement factors varying with sediment particles, and corrects the defects in the derivation of theoretical formulas about viscous coefficient. On the basis of Einstein classical formula, the quantitative relationship between the viscosity coefficient of muddy water and the sediment concentration is obtained. Moreover, Einstein classical formula is the special case of this quantitative expression. The applicability and limitation of the deduced formula for calculating viscous coefficient are verified and discussed with the data gained from the viscosity measurement experiments.
Response of Erosion and Deposition in Ningxia-Inner Mongolia Reach to the Application of Long-Liu Reservoiron the Upper Yellow River
Authors: Zheng Yanshuang , Feng Qing , Zhang Xiaohua , Xiao Qianlu 
Published: November 2019

Abstract
Along with the global and regional climate change and the intensification of human activities, the run-off of the Yellow River basin has been reduced remarkably, bringing serious problems to the local economy and river ecology. In order to point out important scientific issues of human activities, especially the operation of large- sized reservoirs to the changes of scour and fill of Ningxia-Inner Mongolia reach and the basin management, the paper mainly analyzed the influence of human activities (Longyangxia and Liujiaxia reservoirs are called Long-Liu reservoirs for short) to the scour and fill of Ningxia-Inner Mongolia reach. It used the method of hydrologic and hydrodynamic computation model of Ningxia-Inner Mongolia reach, took the observed silt-discharge data of 1968~2004 to prepare a calculation plan of with or without the joint operation of Long-Liu reservoirs and quantitatively evaluate the influence of the operation of Long-Liu reservoirs to the channel scour and fill amount of Ningxia-Inner Mongolia reach. The outcomes show that the joint operation of Long-Liu reservoirs has increased the sedimentation of the reach. During the joint operation of the period of 1987~2004, comparing with the conditions of with and without Long-Liu reservoirs, the total sedimentation of the reach has increased 170 million tons, of which, 363 million tons increased in flood season and 193 million tons decreased in non-flood season. The research results can provide technical reference to the harnessing of Ningxia-Inner Mongolia reach of the upper Yellow River and have an important role in the Yellow River basin management.
Automatic Generation Algorithm of Distribution Network Topology Map Based on GIS Drawing
Authors: Shang Longlong , Hu Ran , Ci Hai , Zhang Wei , Ouyang Guang 
Published: November 2019

Abstract
In view of the inaccuracy and completeness of the distribution network system diagram in the current power grid, the power network structure and the business characteristics of the power industry are investigated and analyzed. The relationship model between substations is analyzed, and the inheritance circuit layout design idea is applied to the distribution. In the grid system topology diagram. The paper proposes a method of dividing the power supply area according to the line contact relationship, and develops an equal density constrained space layout algorithm. Make full use of the distribution network geographic information (GIS) drawings, carry out the power grid topology and line information maintenance, so that the system diagram covers all electrical equipment on the GIS, and can carry out the original electrical topological relationship of the gemstones, and realize the absence of each subsystem. The seams provide image support for a variety of applications. The experimental results show that the proposed spatial topology algorithm is efficient and easy to implement.
Synthesis, characterization of Mg/Mn substituted Ni-Zn ferrites and mechanism of their visible light photo catalysis of Methylene Blue and Rhodamine B dyes under magnetic influence
Authors: George Lovely , Viji C , Maheen M , Mohammed E M 
Published: November 2019

Abstract
Rare earth doped spinel ferrites belonging to the series Ni0.6Zn0.2Me0.2GdxFe2-xO4 (where Me = Mg/Mn, x = 0/0.06) were synthesized by sol-gel method. The characterizations of the prepared samples were performed using X-rayDiffraction (XRD), High Resolution Transmission Electron (HRTEM) Microscopy, Vibrating Sample Magnetometry (VSM), X-ray Photoelectron Spectroscopy (XPS) and Open aperture z-scan technique. The XRD patterns confirm the crystallization of the ferrites in cubic form with spinel structure. The average crystallite size calculated using Debye–Scherrer’s equation is in 10–20 nm range. The HRTEM images reveal the formation of spherically shaped agglomerated nanoparticles. The magnetic parameters such as remanence magnetization (Mr), coercivity (Hc) and saturation magnetization (Ms) were obtained from the hysteresis curves. The samples show better optical limiting parameters than reported which make them promising materials for non-linear applications requiring low limiting thresholds. Owing to their low band gaps ferrites can be efficiently used for the photo catalysis of organic dyes with visible solar energy which constitutes a major portion of sunlight. Ferrites have an added advantage by virtue of their spinel lattice which makes available extra catalytic sites. In the present work, the photocatalytic activity under visible sunlight irradiation was explored from the degradation of Methylene Blue (MB) and Rhodamine B (RhB) dyes. Higher photocatalytic efficiency was exhibited by magnesium containing samples. Near total decolouration of dye solution subjected to magnetic separation has not been reported before. The improvement in photocatalytic degradation efficiency is due to the adsorption followed by effective separation and prevention of photo generated electron-hole pair recombination for a longer period by these ferrites. To further aid the degradation, H2O2 was added as precursor to the reactive mixture which increases the formation of hydroxyl radical (OH·).
Effect of heat treatment conditions on stamping deformation and springback of 6061 aluminum alloy sheets
Authors: Wang Guan , Zhu Guangxu , Kou Linyuan , Li Ting , Liu Zhiwen , Shang Xin , Jiang Xiaoxia , Zhu Xuejun 
Published: November 2019

Abstract
The stamping deformation and springback of the 6061 aluminum alloy sheets under different heat treatment conditions were investigated by three-point bending tests. A validated reliable finite element (FE) model was used to further reveal the springback mechanism. It was found that the heat treatment conditions have great influence on the stamping deformation and springback of 6061 aluminum alloy sheets. The most severe local deformation occurred at the punch position of the T6–8 h alloy sheet, showing minimum bending radius and thickness. However, the bending radius and thickness of the homogenization treated (HT) alloy sheet were maximum, resulting from more materials participate in bending deformation. The HT and solution treated (ST) alloys exhibited higher stamping performance than that of the natural aged (NA) and T6 alloys. The material strength of the T6 alloys can be improved by aging time, motivating greater springback and neutral layer offset. The springback and neutral layer offset of the T6–8 h alloy sheet were the highest, while the HT alloy sheet was the lowest. Furthermore, the effect of material parameters on stamping deformation and springback of sheet was studied by combining with theoretical analysis and experimental results. The research showed that the bending radius and thickness of the sheet in the fillet region increase with the increase of strain-hardening exponent and elongation and with the decrease of yield ratio. After unloading, springback angle and radius increase with the increase of yield strength and strength factor and with the decrease of strain-hardening exponent. These achievements may serve as a guideline for enhancing stamping performance and reducing springback of the aluminum alloy sheet in bending process.
Investigation of the effect of multi wall carbon nano tubes on the dynamic characteristics of woven kevlar/carbon fibers-polyester composites
Authors: Aubad Mohammed Jawad , Abass Basim Ajeel , Shareef Saif Nidhal 
Published: November 2019

AbstractThis research offers an experimental and numerical study on the influence of multi-wall carbon nanotubes (MWCNTs) addition with different weight fractions on the dynamic characteristics of the unsaturated polyester (UP) reinforced by hybrid laminate composites. The laminate composites were prepared for only three layers as a total number of layers in such composites using Kevlar fibers and/or carbon fibers with different volume fractions. Both types of fibers were in the form of plain woven at (0°/90°) angle direction. Hand lay-up method was used to prepare the test samples. It was found that The best mechanical and dynamic properties based on the experimental study have been obtained for unsaturated polyester reinforced with (MWCNTs) particles at weight fraction (0.4% wt). Composite material made of unsaturated polyester reinforced with (MWCNTs) particles was also prepared with the same weight fraction of MWCNTs. Finite element method was used to model the free vibration of a cantilever beam made of composite material. ANSYS software composite Prep-Post (ACP) integrated within ANSYS Workbench software (18.2) was used to solve the FE problem. Field emission scanning electron microscopy (FESEM) and scanning electron microscopy (SEM) are applied to check the morphological properties of the composite material and the dispersion of MWCNT nanoparticles in the polymer matrix. Experimental and numerical Results obtained in the present work showed that the natural frequency and damping ratio of nano composite specimens increase with increasing weight fraction of MWCNTs. The results also showed that composite and hybrid composite materials with (0.4% wt) MWCNTs have higher values of natural frequency and damping ratio. It was found that the natural frequency for the hybrid nano composite with stacking sequence (UP + K/K/K + MWCNT) increased by about 10.4% when adding MWCNTs compared with (UP + K/K/K) laminated composite while it becomes 13.82% and 5.8% for (UP + K/C/K + MWCNT) and (UP + C/K/C + MWCNT) hybrid nano composite material in comparison with that without MWCNTs. The increase percentages of the damping ratio of the such materials have been calculated and it was found to be, 12.23%, 15.9% and 8.6%, respectively. An agreement between the experimental and numerical results has been obtained from flexural and vibration tests with maximum errors not exceeded 3.4% and 9.34%, respectively.
Structural and electronic properties of chemically functionalized SnC monolayer: a first principles study
Authors: Hoat D M , Naseri Mosayeb , Ponce-Péreze R , Hieu Nguyen N , Rivas-Silva J F , Vu Tuan V , Tong Hien D , Cocoletzi Gregorio H 
Published: November 2019

Abstract
We investigate the chemical functionalization effect on the structural and electronic properties of SnC monolayer using first-principles calculations. Specifically, the chlorinated-, fluorinated- and Janus-functionalized monolayers are considered. Based on our calculations, the pristine SnC monolayer is dynamically stable with a planar structure. Its electronic band gap calculated with the HSE06 hybrid functional is 2.371 eV. The inclusion of halogen atoms (F and Cl) destroys the planarity and transforms the hybridization from sp
2 to sp
3. The half-halogenation induces the metallization of the SnC monolayer, while the indirect-to-direct band gap transition can be reached by means of the full-halogenation and Janus-functionalization. Results show that the pristine SnC monolayer electronic structure can be effectively modulated by the chemical functionalization. Therefore, we hope that results presented herein can be of good reference for the SnC monolayer practical applications as well as other 2D materials.
Effect of processing conditions on the microstructure of microcellular PP/WF composites prepared by the continuous extrusion molding technology
Authors: Wang Suwei , Chen Ke , Jia Mingyin , Xue Ping 
Published: November 2019

Abstract
The polypropylene (PP) and wood flour (WF) were mixed first and then extruded by a single-screw extruder foaming system to prepare the microcellular wood-polymer composites (WPCs) in this article. In addition to PP and WF, polyolefin elastomer (POE), talc powders and other fillers were also added to improve the cell structures of the samples. And two types of PP resins were introduced to the formulation of the composites to study the effect of the molecular chain structure on the rheological properties of the samples. Besides, the effects of processing conditions, such as die temperature and screw speed, on the properties of the samples were also investigated. The experimental results indicate that compared with PP1, the complex viscosity of PP2 decreased faster with the shear rate because of the linear molecular chain structure. Besides, the maximum impact strength of PP2/WF composites was 138.5 % higher than that of PP1/WF composites, while the tensile and flexural strength of PP2/WF composites were much lower. In addition, the best microcellular structure and the maximum impact strength were also obtained with the die temperature of 190 °C and the screw speed of 2 rpm.
Biochar-iron composites as electromagnetic interference shielding material
Authors: Akgül Gökçen , Demir Burak , Gündoğdu Ayşenur , Türk Ahmet Serdar , Sözer Sözer 
Published: November 2019

Abstract
Electromagnetic waves emitted by electrical and electronic devices constitute interference with each other, which becomes a problem for security devices, space vehicles, ships, electronics or even human beings. Electromagnetic interference (EMI) protective materials are being developed to eliminate such negative effects of electromagnetic waves. Especially carbon-based ones are becoming increasingly important. The carbonized material biochar, derived from biomass, emerges as a sustainable, renewable, environmentally friendly and inexpensive EMI material. In this study EMI protective effect of biochar derived from industrial tea waste biomass and its iron composite was investigated. The effect values of the samples were found to be greater than 10 dB.
Periodic energy decomposition analysis for electronic transport studies as a tool for atomic scale device manufacturing
Authors: Mathew Paven Thomas , Fang Fengzhou 
Published: November 2019

Abstract
Atomic scale manufacturing is a necessity of the future to develop atomic scale devices with high precision. A different perspective of the quantum realm, which includes the tunnelling effect, leakage current at the atomic-scale, Coulomb blockade and Kondo effect, is inevitable for the fabrication and hence, the mass production of these devices. For these atomic-scale device development, molecular level devices must be fabricated. Proper theoretical studies could be an aid towards the experimental realities. Electronic transport studies are the basis to realise and interpret the problems happening at this minute scale. Keeping these in mind, we present a periodic energy decomposition analysis (pEDA) of two potential candidates for moletronics: phthalocyanines and porphyrins, by placing them over gold substrate cleaved at the (111) plane to study the adsorption and interaction at the interface and then, to study their application as a channel between two electrodes, thereby, providing a link between pEDA and electronic transport studies. pEDA provides information regarding the bond strength and the contribution of electrostatic energy, Pauli’s energy, orbital energy and the orbital interactions. Combining this analysis with electronic transport studies can provide novel directions for atomic/close-to-atomic-scale manufacturing (ACSM). Literature survey shows that this is the first work which establishes a link between pEDA and electronic transport studies and a detailed pEDA study on the above stated molecules. The results show that among the molecules studied, porphyrins are more adsorbable over gold substrate and conducting across a molecular junction than phthalocyanines, even though both molecules show a similarity in adsorption and conduction when a terminal thiol linker is attached. A further observation establishes the importance of attractive terms, which includes interaction, orbital and electrostatic energies, in correlating the pEDA study with the transport properties. By progressing this research, further developments could be possible in atomic-scale manufacturing in the future.