bluuebunny/crossref_metadata_2025_split huggingface dataset:
A coupled excavation and rainfall-induced loess landslide in Liuwanjia Village,Yan’an China: Case study of Middle Pleistocene loess slopes
Authors: Fan Zhongjie , Meng Zhenjiang , Ren Hongyu , Peng Jianbing , Pei Xiangjun , Dong Linyao , Du Jun , Zhang Hongya 
Published: October 2019

Abstract
Loess Plateau is one of the natural test sites to carry out the research of hazards induced by human activities. The loess landslide at Liuwanjia, Yan’an City, Shaanxi Province of China was observed to occur after continuous excavation and rainfall. The Liuwanjia landslide was selected as a case study and then detailed field mapping, 3D laser scanning and laboratory tests were carried out to study the formation characteristics and mechanism of this type of landslide. Based on the analysis of field investigation, excavation was a direct causing factor and the rainwater was a significant influencing factor in the formation of the landslide. The unloading fissures caused by excavation were preferential paths for infiltration of rainwater. Soil compression in the slope induced by excavation and the infiltration of rainwater played an significant role in the formation of local failure. Finally, the formation mechanism of Liuwanjia landslide has been discussed.
Differences in carbonaceous aerosol of fine particles between haze and non-haze days, Beijing
Authors: Liu Qingyang 
Published: October 2019

Abstract
In order to illustrate the factors dominating haze events over Beijing occurred in January, 2013, ambient fine particulate matter (PM2.5, particles with aerodynamic diameter less than or equal to 2.5 μm) samples were collected from January 16 to 31, 2013 at an urban area of Beijing. Daily meteorological parameters including atmospheric pressure, temperature, wind speed, and relative humidity (RH) were recorded. Carbonaceous aerosols in PM2.5 including elemental carbon, organic carbon, PAHs, n-alkanes and levoglucosan were determined to compare the concentration differences between haze days and non-haze days. Associations between PM2.5 carbonaceous aerosols and meteorological parameters were examined. Significant increases of carbonaceous aerosols are found in haze days than those in non-haze days, indicating primary emission sources play a role in haze events occurred in January, 2013. Meteorological parameters do not correlate with carbonaceous aerosols, supporting the regional transport is not dominant factor controlling haze formations. Our results show the primary emissions and meteorological conditions co-contribute the haze formation in Beijing during the sampling period of January, 2013.
Holiday effect of sulfur dioxide concentration in Sanming City, Fujian Province
Authors: Liao Xiaoli , Jin Shaofei , Wu Yonghong , Liu Youwen 
Published: October 2019

Abstract
Sulfur dioxide (SO2) is a common air pollutant. Excessive SO2 can have adverse effects on human health. SO2 emissions are not only affected by industrial production, but also from people’s daily life. This study used the daily data of sulfur dioxide in Sanming City from 2015 to 2018 to analyze the holiday effect on the SO2 concentration in Sanming City. The results showed that the concentration of summer and autumn working days in Sanming City is greater than that of holidays; the concentration of holidays in spring and winter is higher than that of working days. The proportion of sulfur dioxide concentration in the Spring Festival holiday in the year of 2015-2017 is increasing year by year. This study reveals the holiday effect of sulfur dioxide concentration in Sanming City, which has important practical significance for controlling sulfur dioxide pollution in Sanming City and improving the quality of local atmospheric environment.
Analysis on the temperature results of thermal infrared remote sensing based on a ground platform
Authors: Yuan Xu , Meng Qinglin 
Published: October 2019

AbstractThermal infrared cameras have been widely used to measure temperature as a non-invasive measuring instrument recently. To assess the temperature results of thermal infrared remote sensing, we compared them with the temperature obtained by traditional contact temperature measuring method. A ground remote sensing platform was designed to obtain the thermal infrared temperature of the underlying surface. Meanwhile, the traditional contact method was used to obtain surface temperature synchronously. Afterward, the two kinds of temperature were compared and analyzed. Our results indicate that for the four kinds of underlying surface studied in this paper, the two kinds of temperature all have strong correlation. Furthermore, the mean temperature difference ranges between 0.46 °C and 1.79 °C. Moreover, no significant difference can be observed between the two kinds of the temperature of grassland, tile, and permeable brick when the evaluation is at the level of P = 0.001.
HCHs and DDTs in the Bohai Sea: Contamination, distribution and sources
Authors: Song Qiuyang , Luo Wei , Wu Guanghong 
Published: October 2019

Abstract
Concentrations, distributions, and potential sources of DDTs and HCHs in seawater, sediments, soils, and atmosphere were collected to review their pollution statuses in the Bohai Sea and its coastal areas. In comparison to various sediment and seawater quality standards, DDTs and HCHs in sediments and seawater were at low levels in the entire Bohai Sea and might not cause adverse biological effects. However, DDTs and HCHs levels in various sea areas were closely associated with local pesticides production and application as well as hydrodynamic. DDTs and HCHs showed an obvious spatial distribution pattern. High levels were found in the Bohai Bay, Haihe River and Yellow River estuary. DDTs and HCHs concentrations in river and estuary sediments were higher than sea sediments and a seaward decreasing trend was observed. Although HCHs and DDTs residues in the Bohai Sea primarily originated from river runoffs (pesticide factory wastewater, historical applications and residues of technical HCH and DDT, etc.), additional sources of lindane and dicofol existed. Runoff from the demolished old pesticide factories might be another source. Further researches are highly recommended on pollution hotpots of DDTs and HCHs and investigate their migration and transformation at sediment-water interface and pollution history from sediment depth profiles.
Study on economy of flue gas ultra-low emission in coal-fired power
Authors: Zhang Yang , Liu Qingsong , Wei Hongge , Du Zhen , Zhu Yue 
Published: October 2019

Abstract
Along with the rapid progress of flue gas ultra-low emission reconstruction in coal-fired power plants in recent years, flue gas pollutant control is markedly improved, but the economic efficiency of flue gas ultra-low emission was undervalued. Given the present situation of flue gas ultra-low emission in coal-fired power plants, several typical problems about economic efficiency have been analyzed and discussed, including coordinated optimization operation, emissions target control, energy efficiency management on the basis of extensive and thorough investigations. Relevant guidance and countermeasures are proposed to provide further reference for subsequent operation and maintenance of power generation enterprises.
Landscape applications of rainwater resources in urban green space: A case study of green space reconstruction along Riverside Street in Suzhou
Authors: Zhao Wenjing , Ma Jianwu 
Published: October 2019

Abstract
The environmental problems exposed by the process of urbanization have become increasingly serious. At present, China has realized that rainwater is an important and valuable resource. Many cities have successively carried out the mode of rainwater resource utilization.This paper attempts to explore the design of rainwater management into landscape design, transforming from a single engineering technology level to a sustainable ecological level. From the source control, route transmission, terminal storage and storage, the three systems summarize the design of rainwater resources landscape application. Taking urban green space as the research object, and taking the reconstruction of the riverside green space in Suzhou as an example, the advantages and existing problems are analyzed. The feasibility of rainwater management is qualitatively analyzed and the rainwater runoff is quantitatively analyzed. The two measures of surface improvement and rainwater storage are used to explain how to integrate these design methods into specific cases, aiming for the future. Rainwater management in urban green space provides successful experience of others to go by.
Analysis and evaluation of heavy metal pollution in agricultural soils in six cities of Hunan Province, China
Authors: Yu Yang , Sun Cong , Zhang Linlin , Xu Renji , Zhu Yuanyuan , Wu Guoping , Wei Fusheng 
Published: October 2019

Abstract
Environmental problems caused by the exploitation of mineral resources are worsening, especially the heavy metal pollution in soil. Food safety caused by heavy metal pollution in soil has become the focus of increasing attention.Sampling points were selected in Hunan Province. By sampling the soil and rice point by point, the total concentration and the concontration in rice were monitored. The results showed that the mean concentration of Cd, Cu, Hg, Pb and Zn were 1.31 mg/kg, 45.3 mg/kg, 0.61 mg/kg, 49.15 mg/kg and 133.3 mg/kg. The soils were contaminated in some parts of the 85 investigated sites in Hunan Province.Also, the analysis results showed that the average of PI (pollution index) descended in the order of Cd (2.58) > Hg (1.05) > Cu (0.52)> Zn (0.51)> Pb (0.41).The NIPI values of the research area were 28.59, belong to the high-level pollution, which mainly caused by Cd. The pollution ratio of soil samples were 100.0% in Zhuzhou-Xiangtan and Changning, 94.1%, 90.9% and 88.2% in Changde, Yiyang and Yongzhou. According to the potential ecological risk evaluation result, there was a medium level risk in the investigation area of Hunan and the potential ecological risk mainly caused by Cd.
Fine interpretation by using the VMD-based Instantaneous centroid estimation method for a marine carbonate gas reservoir
Authors: Xue Yajuan , Cao Junxing , Wang Xingjian 
Published: October 2019

Abstract
We apply the variational mode decomposition (VMD)-based instantaneous centroid estimation method for interpreting a 11-meters main gas-producing interval of the Longmenshan foreland basin, China. Five VMD-based instantaneous centroid slices are generated for fine interpretation. The results are evaluated by the measured well data. The application results show that the VMD-based instantaneous centroid estimation method targets the 11m main gas-producing interval very well. Field data application shows that the VMD-based instantaneous centroid estimation method can give a fine interpretation of hydrocarbon-related information with high-precision.
Experimental study on recharge capacity of a mixed well injection in Xi’an
Authors: Zhang Xuezhen , Huo Aidi , Wang Jucui 
Published: October 2019

Abstract
The over-exploitation of groundwater can be controlled and prevented by using mixed well to recharge groundwater. A seepage model of semi-confined aquifers was established for simulating recharge well in a cone of depression. Two mathematical expression formulas were proposed for estimating recharge capacity. To analyze the response of recharge capacity, stepwise injections were introduced. It can be pointed out that recharge capacity increases with that of injection flow; moreover, it tends to attenuate during steady injection, which is closely related to injection flow. An attenuation equation of recharge capacity was constructed finally. Recharge capacity was not related to injection mode. The results indicate that under similar conditions, recharge capacity of a mixed well was about one-third of pumping capacity. A minimum value of recharge capacity was maintained with constant injection. Mixed wells were used to recharge and recover groundwater from the cone of depression.
Evaluation of weathered crust reservoirs in buried hills in western uplift belt of JB block in Indonesia
Authors: Zhu Houqin , Li Zenghui , Hong Guoliang , Ma Yuxia , Bai Zhenhua 
Published: October 2019

Abstract
After nearly 20 years of exploration, the western uplift belt of the JB block is now at a high exploration level, and the buried hill has become another new exploration area besides lithologic traps. On the basis of the results of well logging of 17 wells, core of 6 wells and logging interpretation of 17 wells, the differences in the vertical texture features of the basement reservoir are fully considered. According to the differences of logging and seismic response characteristics of 500 km2 between weathered zone and the fractured zone, the colored inversion technique and spectral imaging technique combined with seismic attribute technology are used to predict the plane distribution of porous reservoir in weathered crust. The pre-stack elastic wave impedance inversion technique is preferred for oil-gas-bearing detection evaluation. The results show that the lithology of the B paleo-uplift is granite, and that of the P paleo-uplift is phyllite. The vertical zoning of the buried hill reservoir is obvious, which can be divided into weathered crust zone, fractured zone and tight zone from top to bottom. From the top of the weatheredzone to the fractured zone, the porosity becomes smaller gradually, and distributes in the shape of the discontinuous strips laterally. The planar distribution of the pore-type reservoirs in the weathered zone is obviously controlled by the paleo-structure, and is in the shape of strips and flakiness with obvious zoning characteristics. The porous reservoir is relatively developed onthe crest of the paleo-structure, and the weathered crust reservoir quality of B uplift is superior to that of the P uplifts. Hydrocarbon mainly distributes in the high parts of the two paleo-structures in the shape of strip and flakiness. The results provide a scientific basis for the follow-up drilling decision-making.
Evolution of Cr, Cu, Mn, and Zn during the composting process of chicken manure and their integrated potential ecological risk assessment
Authors: Fan Liangqian , Miao Jiaxin , Yang Jingrui , Zhao Xiaoqing , Xie Maozhu , Shi Weijuan , Cai Jie , Ding Weike 
Published: October 2019

Abstract
The aim of this study was to ascertain the evolution of Cr, Cu, Mn, and Zn during the composting process of chicken manure and their integrated potential ecological risk. This study detected the total amounts of Cr, Cu, Mn, and Zn in 4 samples collected at four different stages in the composting workshop of an intensive chicken farm in Chengdu, China. Furthermore, the chemical fractionation of the four heavy metals was analyzed by the BCR (European Community Bureau of Reference) three-step sequential extraction procedure for each sample. At last, the integrated potential ecological risk of Cr, Cu, Mn, and Zn in the compost at four different stages was evaluated by the procedure of potential ecological risk assessment based on its results of chemical fractionation of Cr, Cu, Zn, and Mn. During the composting process, the total amounts of Cr, Cu, Zn and Mn presented an increasing trend, significantly. Nevertheless, the residual fraction (Res-F) percentage of Cr, Zn, and Cu increased, and the acid extractable fraction (Aci-F) percentage of Mn decreased. The value of integrated potential ecological risk of the four heavy metals in the final product was 9.91. These results indicated the integrated potential ecological risk of the four heavy metals is low. This study provided a support on the promotion and utilization of compost for the intensive chicken farms in China.
Experimental study on oxidation mechanism of pyrite under acidic conditions
Authors: Shi Hong , Zhang Yongbo , Liu Qiang 
Published: October 2019

Abstract
In this study, pyrite samples from the Yankan Coal Mine near the Shandi River in Yangquan City were studied in an oxidation dissolution experiment. Pyrite was studied at different solid-liquid ratios (1:100, 1:50, and 1:20), and the oxygen concentration used was equal to the value in the ambient environment, about 20.95% of the air volume. The pH, oxidation-reduction potential (Eh), and soluble salt concentration (EC), total iron concentration, and SO4
2− concentration in the solution at different reaction times were measured with respect to time. The oxidation reaction rate of pyrite was calculated using the SO4
2− concentration and the factors influencing the oxidation rate at different conditions were discussed. The experimental results showed that, after pyrite was oxidized and dissolved at solid-liquid ratios of 1:20, pyrite decrease from acid generation of the SO4
2−formation, then the pH of the solution increased, at solid-liquid ratios of 1:100, 1:50, and 1:20, the overall Eh and EC values decreased. No matter what solid-liquid ratio is adopted for the reaction, the Fe2+ concentration is higher than Fe3+ concentration, and the Fe2+ and total iron concentration all increase with the increase of solid-liquid ratio, while Fe3+ gradually increases, reaching a trend of relatively stable and slowly decreasing. The average apparent release rate of Fe was proportional to the different solid-liquid ratios. The oxidation reaction rate of pyrite under acidic conditions was directly related to the concentration of reactants, and a faster oxidation rate was observed at higher concentrations due to the larger reaction contact area.
Study on pre-splitting blasting technology of hard roof face
Authors: Liu Huaifu , Xu Zunyu 
Published: October 2019

Abstract
In order to solve the problems of hard roof caving and overhanging area in 220116 working face of Xinji No.2 Coal Mine, deep-hole pre-splitting blasting overburden technology is adopted to destroy the integrity of roof in advance so as to make it collapse as soon as possible, reduce the apparent strength of rock pressure of initial weighting, and slow down the destructive effect of initial weighting on support. The numerical simulation shows that the first collapse step of the basic roof is obviously reduced after the forced roof caving, which greatly reduces the impact disaster caused by large area roof weighting, is conducive to the stability of the support and roof safety management, and is of great significance to the safety production of the working face.
A Comparative Analysis of Different Turbulence Models for Simulating Complex Turbulent Separated Flows over Cubic Geometries
Authors: Praliyev Nurgeldy , Sarsen Aydarkhan , Kaishubayeva Nazira , Zhao Yong , Fok Sai Cheong , Teh Soo Lee 
Published: October 2019

Abstract
This study is aimed to compare the performance of four Reynolds Averaged Navier Stokes (RANS) turbulence models in simulating complex flow over two- and three-dimensional (2D and 3D) cubic geometries using experimental measurements for model validation. The four turbulence models were k-Epsilon (k-ε), k-Omega (k-ω), Shear Stress Transport (SST) and BSL Reynolds Stress (RSM) models. The model validation was performed by comparative analysis with the experimental values of pressure coefficient around the cubic geometries. It was found that the SST and BSL RSM models performed better than the others in capturing the complex separated flows and strong shear in the boundary layer. The good agreement with empirical data can be attributed to the inclusion of transport effects of turbulence and the anisotropic nature in the formulations of the models.
Research on Test Technology of Ionizing Radiation Effect of Spacecraft Material
Authors: Man Li , Yuming Liu , Chunqing Zhao , Kai Zhang , Xiangpeng Liu , Yun Xu 
Published: October 2019

Abstract

60Co γ-ray source and 45keV electron source are used as radiation sources respectively to study the ionizing radiation effect of spacecraft material heat-shrinkable sleeve, and compare the radiation effect similarities and differences between the two radiation sources. The results show that in the damage mechanism, both γ-rays and electrons cause ionization and excitation of electrons outside the nucleus in the material, producing ionization effects, and resulting in degradation and cross-linking of the molecular chains of the material. However, in terms of macroscopic mechanical property degradation, γ-rays can cause complete loss of mechanical properties of material, while 45keV electrons only cause partial damage to the mechanical properties of the material. In addition, at the same dose, γ-rays can damage the mechanical properties of the material to a greater extent than 45keV electrons. This paper explains the phenomenon and puts forward the applicable conditions of the two test technologies.
Influence of Sampling Frequency in DCPD Crack Monitoring
Authors: Zhang Liang , Xue He , Ni Chenqiang , Gou Siyu 
Published: October 2019

Abstract
Due to the particularity of autoclave environment, it is difficulty to real-time monitor the crack growth state in the autoclave, and Direct Current Potential Drop method (DCPD) is widely in the crack propagate monitor in this kind experiment. The signal characterized by DCPD method is usually submerged by strong noise. In this paper, the extraction and filtering methods of crack characteristics in high temperature and high pressure environment are studied. The SINC filter is used to obtain crack initial data information and filter out the pulse interference signal, and the FIR filter is used to filter out high frequency interference. Finally, crack monitoring experiments at different sampling frequencies were studied. The experimental results show that the sampling frequency has a great influence on the stability and anti-interference ability of the data.
A Liouville theorem for supersolutions of linear elliptic second-order partial differential equations
Authors: Kurta Vasilii 
Published: October 2019

We study supersolutions of linear elliptic second-order partial differential equations of the form

(

∗

)

L
u
:=

∑

i
,
j
=
1

n

(

a

i
j

(
x
)

u

x
i

)

x
j

=
0
,

\begin{equation*} Lu:=\sum \limits _{i,j=1}^n (a_{ij}(x)u_{x_i})_{x_j}=0,\tag *{($\ast $)} \end{equation*}

which are defined and measurable in the whole space

R

n

{\mathbb R}^n

, and which belong locally to a Sobolev-type function space associated with the operator

L
L

defined in

R

n

{\mathbb R}^n

,

n
≥
2

n\geq 2

. We assume that the coefficients

a

i
j

(
x
)

a_{ij}(x)

of the operator

L
L

are measurable, locally bounded and such that

a

i
j

(
x
)
=

a

j
i

(
x
)

a_{ij}(x)=a_{ji}(x)

, and that the quadratic form associated with the operator

L
L

is positive-definite. We prove a Liouville theorem for supersolutions of (

∗
\ast

) defined in

R

n

{{\mathbb R}^n}

, in terms of a capacity associated with the operator

L
L

. As well, we establish a sharp distance at infinity between any non-constant supersolution of (

∗
\ast

) in

R

n

{{\mathbb R}^n}

bounded below by a constant and this constant itself, also in terms of the capacity associated with the operator

L
L

.