bluuebunny/crossref_metadata_2025_split huggingface dataset:
Melting scenario affects the dynamics of polycyclic aromatic hydrocarbons released from snowpack
Authors: Liu Shasha , Wang Zucheng , Xu Xiaoyun 
Published: February 2020

Abstract
Melting snowpack can release semi-volatile organic contaminants (SVOCs) to both terrestrial and aquatic ecosystems, resulting in high ecological risk. The dynamics of polycyclic aromatic hydrocarbon (PAH) released from snowpack under controlled laboratory (intense melting) and field (melt/freeze melyting) snowmelt experiments was investigated in this study. In the laboratory: dissolved organic carbon (DOC) controlled the first flush of dissolved PAHs released from snowpack, except for napthelene, which is also affected by its solubility. The particles released early from snowpack usually contained high PAH concentrations (more than 100 μg g−1) and those released at the end contained low PAH concentrations (<20 μg g−1). The total PAH release pattern was determined by composition of all PAHs, including type 2 enrichment with a final peak and type 4 enrichment with double-peak. In field melting: all dissolved PAHs were released constantly, except naphthalene, which also showed a first flush but to a lesser extent. DOC controlled the release pattern of all detected dissolved PAHs from snowpack. High PAH concentrations were observed in particles released from snowpack at both the beginning and the end of the melting event. Concentrations of both total PAHs and PAH compositions in meltwater showed an increasing trend with melting time (from 1.3 to 4.0 μg l−1 and from 1.7 to 5.3 μg l−1 in meltwater from each of the two snowpacks), which coincided with Type 3 enrichment. Overall, our results suggest intense melting of snowpack results in the shift of some hydrophobic PAH compositions from Type 2 to Type 4 enrichment, depending on their partition coefficients. In contrast, melting with melt/freeze cycles may cause the shift of PAHs from Type 2 to Type 3 enrichment. Our study indicates changes of the melting scenarios due to global warming could affect dynamics of SVOCs released from snowpack, which is useful for risk management for water and soil quality.
Long-term ecological consequences of forest fires in the continuous permafrost zone of Siberia
Authors: Kirdyanov Alexander V , Saurer Matthias , Siegwolf Rolf , Knorre Anastasia A , Prokushkin Anatoly S , Churakova (Sidorova) Olga V , Fonti Marina V , Büntgen Ulf 
Published: February 2020

Abstract
Wildfires are an important factor in controlling forest ecosystem dynamics across the circumpolar boreal zone. An improved understanding of their direct and indirect, short- to long-term impacts on vegetation cover and permafrost–vegetation coupling is particularly important to predict changes in carbon, nutrient and water cycles under projected climate warming. Here, we apply dendrochronological techniques on a multi-parameter dataset to reconstruct the effect of wildfires on tree growth and seasonal permafrost thaw depth in Central Siberia. Based on annually-resolved and absolutely dated information from 19 Gmelin larch (Larix gmelinii (Rupr.) Rupr.) trees and active soil layer thickness measurements, we find substantial stand-level die-off, as well as the removal of ground vegetation and the organic layer following a major wildfire in 1896. Reduced stem growth coincides with increased δ
13C in the cellulose of the surviving trees during the first decade after the wildfire, when stomatal conductance was reduced. The next six to seven decades are characterized by increased permafrost active soil layer thickness. During this period of post-wildfire ecosystem recovery, enhanced tree growth together with positive δ
13C and negative δ
18O trends are indicative of higher rates of photosynthesis and improved water supply. Afterwards, a thinner active soil layer leads to reduced growth because tree physiological processes become limited by summer temperature and water availability. Revealing long-term effects of forest fires on active soil layer thickness, ground vegetation composition and tree growth, this study demonstrates the importance of complex vegetation–permafrost interactions that modify the trajectory of post-fire forest recovery across much of the circumpolar boreal zone. To further quantify the influence of boreal wildfires on large-scale carbon cycle dynamics, future work should consider a wide range of tree species from different habitats in the high-northern latitudes.
Research progress of modified macroporous adsorption resin in adsorption separation
Authors: Sun Tao 
Published: February 2020

Abstract
Macroporous adsorption resin (MAR) is widely used in molecular adsorption and material separation due to its unique porous nature, surface activity and easy modification. Although there may be multiple synergistic effects in the adsorption process, its adsorption capacity is weak, and it is difficult to meet the problem of separation and purification of complex samples. The functional modification of macroporous adsorption resin is an ideal way to improve its separation efficiency and selectivity. In this paper, recent advances in the preparation of modified macroporous adsorption resins and their application in adsorption separation are reviewed, which provides a reference for further research.
Surface/Deep Defects manipulated Fluorescence Properties and LED application of Copper Nanoclusters
Authors: Ai Lin , Li Ji , Tang Min , Chen Hsiaohsien , Meng Hong 
Published: February 2020

Abstract
The contribution of metal defects to the emission enhancement of Cu nanoclusters has been proposed. But the insufficient understanding of the defects luminescence mechanism limits its further effective adjustment and control to the emission color. In this work, the surface metal defects of the assembled fluorescent materials are deliberately engineered. Metal defects have effects on luminescent energy levels, which are relative to the dynamic process of exciton radiation transition and regulate the photophysical properties of the materials. Further studies demonstrate the surface metal defects possess shallow energy level and multi sublevels, broaden the emission colors. Moreover, the continuous alteration of emission color is achieved by simply adjusting the relative ratio of the surface and deep metal defects. Based on the full-color emission of copper clusters, the white light emitting diodes (WLEDs) with different color temperatures (warm, cold, and pure white) are prepared for illumination application.
Chemical Fixed Point Sealing Technology in Oil Well
Authors: Zhang Lili , Yan Haijun , Hao Huijun , Xie Gang , Wei Aijun , Wei Lili , Sun Lei , Wang Hongfeng 
Published: February 2020

Abstract
When most oil fields have entered high water cut stage, the distribution of oil and water is more and more complex. Profile control and water shutoff is an important technology for water control and oil stabilization. Some types of water invasion in special reservoirs such as bottom water coning or edge water propelling in horizontal wells, water invasion in micro facture and big pore carry more challenges for profile control and water shutoff technology. Beyond that this technology is also affected by the plugging agent injection’s uncertainty and migration randomness. On the basis of earlier research, this paper introduces the plugging agent formulas, technology and field application of three types of technologies which are as follows, casing channeling treatment technology, water invasion plugging technology in interlayer and water invasion in horizontal well. The three types of fixed point sealing technology can achieve the accurate injection of shutoff agent and good results had obtained in site test.
Finite element analysis of damage region of CBM well based on underbalance reconstruction technology
Authors: Bao Xitao , Yang Jiang , Yan Yifei , Yan Xiangzhen 
Published: February 2020

Abstract
The reserves of coalbed methane (CBM) in China are very high. But the characteristics of “three low” (low pressure, low permeability, low porosity), thin formation and shallow burial depth for the CBM reservoirs may cause problems of long production cycle and slow increase in production. For above problems, a new reconstruction method for coal bed methane formation named underbalance reconstruction was introduced. By this method, a jet generator was lowered to perforated interval. Then, with the nitrogen injected and blowout, reconstruction results of coalbed reservoir can be achieved. Considered the process of underbalance reconstruction, coalbed reservoir properties and mechanical properties of coalbed, mechanical model of coalbed methane well was built and analyzed by finite element method. Afterwards, damage area of different nitrogen injecting cycle can be characterized. And the effect of underbalance reconstruction for coal bed methane formation can be obtained. Then, parameters of reconstruction technology can be optimized and optimization scheme can be supplied for the underbalance reconstruction for coal bed methane formation.
Analysis of Disaster Gas Accumulation Characteristics in Local Area of Upper Corner Based on Entropy Variable Dissipative Structure Model
Authors: Wei Yin-shang , Liu Pei-yao , Jia Yu-quan 
Published: February 2020

Abstract
This paper takes the angle CO of the 1406 working face of Fengjiata Coal Mine as main research object, by combining field measurement, theoretical research and numerical simulation, to explore essence of energy dissipation during gas accumulation in the upper lag zone and seek effective governance solutions. The result shows that the irreversible process such as eddy current loss caused by the spatial morphology of the upper sag angle is an important cause of gas accumulation. Thus, a flexible inflatable airbag for mining to change local ventilation mode is proposed and designed. The numerical simulation method is used to verify the venting of the mine inflatable airbag, which helps significantly eliminate the eddy current phenomenon in the lag zone.
A Review on the Molecular Mechanism, Superiorities, Appli-cations, Limitations and Experimental Workflow of CRISPR/Cas-9 System, and the Future of Gene Engineering
Authors: Wang Xiaoke 
Published: February 2020

Abstract
Gene engineering has been in development since the 1970s. The appearance of CRISPR/Cas-9 system, a gene engineering technology, even brought the wave of developing to its unprecedented peak. Meanwhile, the drastic growth and maturity of CRISPR made the public, represented by popular presses, to question the integrity and rightfulness of scientists to develop and apply CRISPR system, causing intense worldwide ethical battles of humanity. However, without relative knowledge background, rational and logical judgment can be hard to make. Us-ing qualitative research techniques, this research has thoroughly reviewed previous literatures that introduced the molecular mechanism, superiorities over other technologies, applications and limitations of CRISPR/Cas-9 system in order to give comprehensible introduction for the public. Using quantitative research methods, this research investigated the attitudes came from the pub-lic and science community toward the ethical issues around the use of gene engineering tools such as CRISPR in the form of numerical comparisons. More than 50% of people stand neutral in this battle, but there were more supporters of developing gene engineering technologies in the science community than that of in the public presses, which produces a necessity for countries to call for a pause of current developments, and to assemble national leaders to have a serious discussion.
Study on mechanical properties of cemented filling materials using by low-chlorine fly ash
Authors: Shi Tengyu , Zhang Siqi , Wen Ni , Li Keqing , Wang Ke , Ba Haojing 
Published: February 2020

Abstract
In this study, the blast furnace slag and desulfurized gypsum were used to make cementing materials, mixed with the tailings and fluidized bed municipal solid waste incineration(MSWI) fly ash to make high performance cementing filling material. The results show that: (1) The best ratio of test is low chlorine fly ash: slag: desulfurization gypsum = 20%: 68%: 12%, the MPC of cementing material is 82%, and the cement-sand ratio is 1:4, after curing for 28 days in a standard curing box with a curing temperature of 40°C and a relative humidity of 90%, the compressive strength reaches 22.81MPa, the flow rate reaches 240 mm. (2) The maximum amount of fly ash can reach 60%, after 28 days of curing, the sample strength is 8.70 MPa, the flow rate is 220 mm, both of which meet the requirements. (3) Comparing the slag system and cement system with 60% fly ash, it was found that the strength reached 10.36 MPa after 28 days of curing, the flow rate of the cement system was 215 mm, which did not reach the self-flow standard. It is possible to provide a low cost cementing filling material containing waste incineration fly ash in future.
Alkali treatment of bamboo powder mixed polypropylene and its effect on properties
Authors: Li Chenxin , Guo Weilin , Liu Chen , Shen Taoyi , Chen Tong , Wang Lijun , Kong Linxue 
Published: February 2020

Abstract
Bamboo powder (BP) was treated with different concentrations of alkali solution, and modified polypropylene material of bamboo powder/polypropylene blend was prepared. Using the scanning electron microscopy (SEM) and X-ray diffractometry (XRD) to study the effects of alkali treatment and various alkali concentrations on the micro-structure and mechanical properties of the modified polypropylene. The test results illustrate that the alkali treatment can remove the amorphous cement between lignocellulose, form more fine mesh structure, and increase the surface area, which is beneficial to improve the mechanical interlock between the fiber and the polymer matrix. Thus, improving the mechanics performance of composites by this method. As the increase of alkali solution concentration, the impact strength of bamboo powder/polypropylene composites show the trend of rising up and then descending. When the concentration of sodium hydroxide is 3%, the bamboo powder/polypropylene composite material has better normal temperature impact strength. When the sodium hydroxide concentration is 9%, the bamboo powder/polypropylene composite has the optimal yield strength.
Quantitative determination of Lisinopril Dihydrate in pharmaceutical preparations by direct potentiometriy
Authors: Bozhanov S , Smerikarova M , Maslarska V 
Published: February 2020

Abstract
A direct potentiometric titration method was applied for determination of Lisinopril Dihydrate. The method was based on the treatment of the primary data with nonlinear regression procedure. An accessible and easy-to-use algorithm for the evaluation (quantification) of a system with acid-base properties has been developed to provide a quick and unambiguous answer for the quantitative content of Lisinopril Dihydrate. The acid-base constants of Lisinopril Dihydrate were determined in aqueous solutions (at constant ionic strength 0.2 mol/l KCl and temperature 25°C). The potentiometric method developed was validated according to ICH and shows very good accuracy and precision. The present approach can be successfully used in routine analysis of the drug in quality control laboratories.
Label-free electrochemical aptasensor for GPC3 detection based on RGO-CS-Fc/Pt NPs
Authors: Li Yuqiu , Li Wenzhan , Li Guiyin 
Published: February 2020

Abstract
Glypican-3 (GPC3) is a promising biomarker of early detection of hepatocellular carcinoma (HCC). Herein, an label-free electrochemical aptasensor for the detection of GPC3 was developed based on reduced graphene oxide-chitosan-ferrocene/platinum nanoparticles (RGO-CS-Fc/Pt NPs). GPC3 aptamer (GPC3-Apt) was immobilized onto the surface of the modified screen-printed carbon electrode (SPE) by RGO-CS-Fc/Pt NPs. When the GPC3 was added to the platforms of aptasensor, the specific recognition reaction between the GPC3-Apt and GPC3 produced aptamer-antigen complex and arranged on the electrode surface, which made the change of electrochemical signals of Fc obtained by differential pulse voltammetry (DPV). Hence, the calibration graph (peak current vs GPC3 concentration) can be used for quantification of GPC3. The measured peak current and GPC3 concentration have a good linearity in the range of 0.05-10.0 μg/mL, a correlation coefficient of 0.9805 and a low detection limit of 0.018 μg/mL (S/N=3). Moreover, the designed aptasensor showed good performance with excellent selectivity, acceptable reproducibility and stability. Thus, this label-free electrochemical aptasensor has promising applications for the early detection of HCC.
Low Temperature Catalytic Performance of Manganese and Cerium Complex Oxide Catalyst towards Toluene
Authors: Wang Keliang , Liu Xiuzhen , Tu Shunheng , Zhang Le , Li Wen , Jiang Chan , Ye Daiqi 
Published: February 2020

Abstract
A series of MnOX(X)–CeO2 complex oxide catalysts with various Mn/Ce mole ratios were prepared successfully by sol-gel method and were characterized by BET, XRD, SEM, H2-TPR and XPS techniques, and the catalytic activity towards toluene were tested. The results showed that MnOX(X)–CeO2 complex oxide catalysts presented superior low temperature catalytic activity than pure CeO2 and MnOx, MnOx(0.6)-CeO2 exhibited the highest catalytic activity with T50=125°C and T99=197°C under the condition of GHSV of 10000h−1 and toluene concentration of 100ppm. The characterization results also indicated that the catalytic activity was relavant closely with specific surface area, catalyst morphology and valence of manganese oxides. Also, MnOX(X)–CeO2 formed solid solution with fluorite structure after the introduction of manganese, and produced quantities of manganese species, atom adsorbed oxygen and crystal oxygen, which promoted the adsorption and activation of gaseous oxygen and the mobility and transfer of active oxygen.
Effect of Different Reduction Methods on the Structure of Graphene Oxide
Authors: Feng Ting , Zheng Leilei , Huang Jin , Chu Zhen , Xue Dengrong , Liu Zhongxin 
Published: February 2020

Abstract
The samples of graphene oxide were prepared by Hummers method, and then they were reduced and dried by different methods. The effects of different treatment methods on the graphene oxide’s morphology, size and oxygen content were analysed by IR, Roman and TEM. The results show that the reduction method of increasing temperature can effectively reduce the oxygen content of graphene oxide but increase the defect density. However, the ultrasonic cell pulveriser can effectively reduce the oxygen content of graphene oxide in the reduction process and has little effect on the defect density. Therefore, low-defect and low-oxygen reduced graphene oxide can be quickly obtained by an ultrasonic cell pulveriser.
A label free colorimetric assay for detection of sulfite root based on Cu2+
Authors: Ma Yefei , Fu Xiaofen , He Wen , Gao Xing 
Published: February 2020

AbstractThe reaction between sulfite and hydrogen peroxide causes the absorbance decrease, which provides the basis to determine the sulfite content that is sensitive to the absorbance change. Cu2+can catalyze the chemical reaction between hydrogen peroxide (H2O2) and the 2,2’-Azinobis-(3-ethylbenzothiazoline-6-sulphonate) (ABTS) effectively, which will cause the change of absorbance. In this paper, we presented an experiment system to study the influence of pH value, H2O2content, Cu2+content and reaction time on the reaction system. The comparison of experiment system results indicated that the optimal condition was pH value of 7.0, H2O2of 500 μM, Cu2+of 250 μM and 5 minutes reaction time. Under the optimal conditions, the absorbance (Y) and SO32-content (C) have a linear relationship Y=-861.35C+0.8923. The coefficient of determination (R2) in the linear relationship is 0.9983, which indicates a strong correspondence between C and Y. Then, the established method was used to detect the sulfite in wine. The recovery rate was between 96.01% and 106.90%, which proves this method is efficient for sulfite determination.
A stable FHD display device based on BCE IGZO TFTs
Authors: Wan G M , Ge S M , Gong C , Li S , Lin X N 
Published: February 2020

Abstract
In this work, the impact of the deposition process of the SiOx passivation layer on the electrical properties of the BCE IGZO TFTs has been studied. The ΔVth of the TFTs are 2.52 and -1.67 V under PBTS (60°C, 30 V) and NBITS (60°C, -30 V, 4500 nit) after 1 hour, respectively. The stability of these TFTs is verified in 32in FHD display devices, which still could display the picture properly after the 500-hour aging test at 60°C and 90% humidity. A stable FHD display device based on BCE IGZO TFTs was achieved.
Study on the preparation of suspension stabilizer for liquid accelerator
Authors: Guan Mengqin , Li Xianghe , Guo Xinqi , Jiang Zhuojun 
Published: February 2020

Abstract
A suspension stabilizer (P-XF) was prepared by copolymerization of acrylamide (AM), acrylic acid (AA), ammonium persulfate (APS), thioglycolic acid (TGA) and potassium hydrogen tartrate (KHT). The suspension stabilizer (P-XF), aluminum sulfate (Al2(SO4)3), p-toluenesulfonic acid (PTSA) and triethanolamine (TEA) were used to prepare a liquid accelerator (P-SN2). The test results show that compared with the liquid accelerator (P-SN1) without P-XF, P-SN2 not only can effectively shorten the setting time, but also has high stability, with a stable period of more than one year.
Simulation and application of a new type of slideway beam based on MIDAS jacking construction method
Authors: Qin LI , Gao Jian , Zhang Qiuyue 
Published: February 2020

Abstract
In order to ensure the continuous box girder jacking method in the process of construction safety in Jingzhou City, Mongolia and China Railway Bridge jacking construction method of process engineering background, research on continuous box girder pushing process in the first two layer 8 laminated I-beam spell 56B security control problem model in the process of construction, the slide beam. Based on the control principle of adaptive method, a finite element model of slideway beam during incremental launching is built by MIDAS, and the range of deformation and internal force of the whole structure of slipway beam is put forward during construction. Through monitoring and measuring the deformation of the slideway beam during the incremental launching process, we get the test data and compare with the theoretical value, so as to guide the safety control of the slipway beam during the pushing construction of the continuous box girder. The research results show that during the incremental launching of continuous box girder, the slideway beam can meet the requirements of deformation and internal force. The safety control technology adopted can effectively guide the engineering construction, and the method is feasible.
Description of delaminations in composite multilayered structures – comparison of numerical and experimental results for compressed plates
Authors: Muc A. 
Published: February 2020

Abstract
The buckling loads and the post-buckling behavior of the perfect and imperfect delaminated plate are investigated in the paper. For this purpose the concise formulations enabling to derive pre- and post-buckling behaviour of plates with embedded delaminations is presented. The computations are made using FE package NISA II and Mathematica package. Obtained results for buckling loads and the post-buckling behaviour are compared with the experimental results. The Digital Image Correlation (DIC) technique is employed to verify the uniformity and homogeneity of deformations.