Articles in press have been peer-reviewed and accepted, which are not yet assigned to volumes/issues, but are citable by Digital Object Identifier (DOI).

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Regio- and Chemoselective Fluorination of 1,3-Dicarbonyl Compounds
[Abstract](484) [PDF 0KB](15)
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Highly regioselective α-fluorination of 1,3-dicarbonyl compounds could proceed smoothly by virtue of 1-chloromethyl-4-fluoro-1,4-diazoniabicyclo[2.2.2]octane bis(tetrafluoroborate) as the fluorine source in the mixed solvent of ethanol and water. By adjusting the amount of the fluorine source and reaction time, the desired 2-fluoro- and 2,2-difluoro-1,3-dicarbonyl compounds could also be efficiently constructed with an excellent chemoselectivity. The reaction readily took place via a single electron transfer process at room temperature without any transition-metal catalyst, alkaline additive or additional oxidant and could be applicated in gram-scale synthesis, which features a convenient and practical free-radical fluorination.

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Non-oscillatory Entropy Stable Scheme for Shallow Water Equations
LIU Youqiong, LIU Qingsheng, RONG Xianju, HUANG Fenglin
2019, 32(3): 345-351.   doi: 10.3969/j.issn.1003-0972.2019.03.001
[Abstract](271) [PDF 1707KB](9)
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A low dissipative non-oscillatory entropy stable scheme is presented for shallow water equations. The scheme is given to construct entropy stable flux by addition of the entropy viscosity term of entropy conservative flux into Roe's entropy stable flux, to controlling entropy production at discontinuities, which result have enough entropy dissipative to remove oscillations near discontinuity. Further, high resolution entropy stable flux is constructed for the flux limiter functions. These new fluxes is tested on one dimensional and two dimensional problems, numerical examples demonstrate that these schemes are low dissipative,high resolution and non-oscillatory.
Existence of Solutions for a Class of Quasilinear Schrödinger Equations
ZHANG Ping, HAN Jianxin
2019, 32(3): 352-356.   doi: 10.3969/j.issn.1003-0972.2019.03.002
[Abstract](266) [PDF 331KB](5)
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The existence of solutions for a class of quasilinear Schrödinger equations with coercive potential is investigated. By using the mountain pass lemma, a nontrivial solution is obtained when the nonlinear term is asymptotically linear at the origin and asymptotically triple at infinity.
Analysis of the Asymptotic Properties of a Stochastic Glucose-insulin Regulation System
SHI Xiangyun, YAO Jiaoyan, HUANG Mingzhan
2019, 32(3): 357-361.   doi: 10.3969/j.issn.1003-0972.2019.03.003
[Abstract](247) [PDF 459KB](3)
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A stochastic glucose-insulin regulation system with the perturbation of white noise is investigated. The existence and uniqueness of the positive solution of the system is proved. The asymptotic properties of the positive solution are investigated. There is not a positive equilibrium point for the stochastic system after adding stochastic perturbations to the associated deterministic system. In order to discuss the stability of the system, it is proved that under certain conditions, the solution of the stochastic system will vibrate randomly around the positive equilibrium point of the deterministic system, respectively, and the intensity of this vibration depends on the intensity of the white noise. In addition, the influence of the white noise on system stability is discussed by numerical simulation.
A Giving up Smoking Model with General Nonlinear Incidence Rate
WANG Xia, LI Baolin, GE Qing
2019, 32(3): 362-366.   doi: 10.3969/j.issn.1003-0972.2019.03.004
[Abstract](265) [PDF 333KB](9)
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A giving up smoking model with general nonlinear incidence rate was proposed. The existence and local stability of equilibria are completely determined by the basic reproduction number. The threshold dynamics was established by employing the approach of Lyapunov functional. When the basic reproduction number is less than one, the smoking-free equilibrium is globally asymptotically stable; otherwise, the smoking-present equilibrium is globally asymptotically stable.
Construction of Adaptive Landscape for a Non-gradient System
JIAO Shuyun, WANG Xin, XU Song
2019, 32(3): 367-371.   doi: 10.3969/j.issn.1003-0972.2019.03.005
[Abstract](232) [PDF 454KB](2)
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Based on the two-dimensional non-gradient system, the adaptive landscape is constructed. The qualitative analysis of the system is gotten in the action of selection, recombination and the linkage disequilibrium. And for the first time, through the method of constructing the generalized Lyapunov function, the adaptive landscape is given quantitatively. It is clarified that the detailed balance and zero curl is not the criterion for the existence of the adaptive landscape.
Genome-wide Identification and Expression Analysis of BGLU Family Genes in Soybean
KE Danxia, LIU Yonghui, ZHANG Jingjing, CHEN Qiongjie
2019, 32(3): 372-378.   doi: 10.3969/j.issn.1003-0972.2019.03.006
[Abstract](242) [PDF 3015KB](5)
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In plants, beta-glucosidase (BGLU) is involved in many important physiological processes, including the release of chemicals to resist external invasion, the lignification of cell walls, the activation of plant hormones and plant secondary metabolism. The 42 genes of soybean BGLU family were identified using soybean genome database. The gene characteristics, protein structure, phylogenetic evolution, chromosome localization, promoter regulatory elements and expression patterns of the family members were analyzed comprehensively. These results will provide important genetic information for the future function study of BGLU family genes in soybean.
An Empirical Analysis of Recovery of Motor Function of Female KOA by MRT and FMT
NIU Sen, WANG Weihong, ZHAO Huanbin
2019, 32(3): 379-384.   doi: 10.3969/j.issn.1003-0972.2019.03.007
[Abstract](230) [PDF 472KB](1)
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Forty female with knee osteoarthritis(KOA) were selected as research subjects by using the methods of measurement,experiment,mathematical statistics and other research methods,and were randomly divided into treatment group and functional group,with 20 patients in each group. The treatment group were treated with myofascial release therapy (MRT) by combining with thermotherapy and the functional group were treated with myofascial release therapy (MRT) combined with functional movement training(FMT).The results showed that there were significant differences in active and passive ROM, muscle endurance and WOMAC scores between the treatment group and the functional group before and after the experiment (P<0.01).At the end of the experiment, the evaluation scores of each index in the treatment group changed with the increase of time, and there were significant differences in the evaluation scores of each index during this period of three time (P<0.01),and evaluation scores of the WOMAC in the functional group showed significant differences at the end of half a month after treatment (P<0.05), but there was no differences in other indexes.The results showed that both methods had good recovery effect on female with KOA.
The Effects of Enclosed Exercise for Weight Loss on Physical Health of Obese Adolescents
LIU Tingyou
2019, 32(3): 385-389.   doi: 10.3969/j.issn.1003-0972.2019.03.008
[Abstract](238) [PDF 377KB](1)
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To understand the effects of enclosed exercise for weight loss on physical health of obese adolescents. The 44 cases of 14 to 19 year-old obese adolescents were chosen by us in 6-week enclosed exercise for controlling diet and exercise. Their indicators of body shape, body function, physical fitness, blood health and so on were tested. By means of literature analysis and mathematic statistics to analyze the mathe of experiments. The results showed that through six weeks of enclosed exercise, The obese adolescents have a significant decline in fat mass, weight, body fat rate(P<0.05). Lung capacity of obese adolescents gradually increased, physical fitness indicators endurance, flexibility, 50-metre Race and blood health indicators triglyceride(TG), total cholesterol(TC), fasting insulin(FINS) were significantly improved(P<0.01). The enclosed sports weight loss on the physical health o the obese adolescents good performance.
Study on Microscopic Mechanism of Hollowing in Agricultural Areas from the Perspective of Spatial Distance Clustering: A Case Study of Villages in Five Cities of Henan Province
GAO Junbo, LI Shuqin, ZHANG Qian, WANG Jiabao
2019, 32(3): 390-396.   doi: 10.3969/j.issn.1003-0972.2019.03.009
[Abstract](423) [PDF 1328KB](3)
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Using spatial analysis and mathematical statistics techniques to quantify the spatial distance between the village empty residential land and other villages, and based on factor analysis and clustering,the rural hollowing-out mode of plain agricultural areas and Microscopic mechanism are explored. The results show that the average distance from the rural empty residential land in the plain agricultaral areas of Henan Province to the fields, main roads, village roads and medium-sized residential bases are 84 m, 25 m, 134 m and 19 m, respectively. There are three types of village hollowing mode of traffic-oriented, production-oriented and hybrid, which are the result of the combination of economic factors, location conditions, planning management and rural residents' living concepts. Finally, the countermeasures were proposed from cultivating new rural formats, developing urban and rural large-scale agriculture and innovative institutional mechanisms and policy systems, to promote the utilization of village resources and boost rural revitalization.
Response of Shallow Ground Temperature in the North-South Transition Zone under Global Warming: A Case Study of Xinyang City
YAN Junhui, LIU Jinke, LU Shan, WANG Liming, LIANG Liuling, LIU Minghua, CAO Guangchao
2019, 32(3): 397-402.   doi: 10.3969/j.issn.1003-0972.2019.03.010
[Abstract](419) [PDF 815KB](7)
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Based on the monthly mean surface air temperature and shallow ground temperature data at the depth of 0~20 cm from 1961 to 2017 in Xinyang City, located in central North and South Transition Zone, the temporal characteristics of shallow ground temperature and its response to climate change were analyzed by using the statistical, Mann-Kendall test and power spectral analysis methods. The main conclusions were as follows:(1) During the past 57 years, the annual mean shallow ground temperature for each layer showed a significantly warming trend. (2) Significant periodicity of 2~4 a was detected in annual and seasonal mean ground temperature over the past 57 years, and the quasi-cycles were obvious especially in the autumn and winter seasons. (3) During the early 1990s, there the existed significant abrupt changes in Xinyang ground temperature of 5 cm, 10 cm and 20 cm. However, the ground temperature of 0 cm turned from cold to warm conditions during the late 1990s. (4) The shallow ground temperature was significantly correlated with the surface air temperature in Xinyang. The most sensitive layer to climate change was the surface layer.
Effect of Agriculture Resources Exploitation on the Ecological Environment
CHENG Li
2019, 32(3): 403-408.   doi: 10.3969/j.issn.1003-0972.2019.03.011
[Abstract](234) [PDF 664KB](4)
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Two agricultural tourism resource development zones with similar size that they were on the development and operating, Yiyang Huaxiang farmhouse and Tushengyuan tourism,resort had been investigated. The results showed that the pH value in soil was low, partial acid and the contents of Nitrogen and phosphorus in soil was on the high side. Water in two farmhouses was polluted slightly compared with the national standard, partial acid, contents of Nitrogen and phosphorus in soil was on the high side. On the one hand, the comprehensive pollution index was related to the number of tourists. Detecting atmospheric environment showed that atmosphere environment was varing in different months, the concentration of sulfur dioxide and total suspended particles (TSP) was in the highest levels at the spring and winter, autumn and summer was lower. On the other hand, the pH value of rainfall was in the lowest in spring and winter, lower in autumn and higher in summer. Preliminary inferenced, human activities had the enormous influence to the surrounding ecological environment on the process of development of agricultural tourism resources.
Research on Old Revolutionary Base Area Residents’ Willingness about Participating in Pro-poor Tourism
SHEN Ke, WANG Wenchao, GUO Wenru
2019, 32(3): 409-414.   doi: 10.3969/j.issn.1003-0972.2019.03.012
[Abstract](417) [PDF 632KB](6)
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Taking the old revolutionary base areas of four counties in Henan province as the research area, based on the theory of planned behavior (TPB), the theoretical model of residents' willingness to participate in poverty alleviation through tourism was constructed and tested by using structural equation.The results show that:(1)Subjective norms, perceived behavior control and desire of overcoming poverty directly affect the behavior intention of participating in tourism poverty alleviation.(2)Behavior attitude indirectly influences behavior intention through the desire of overcoming poverty through intermediary variables. (3)Behavior intention affects participation behavior.(4)Perceived behavior control and desire of overcoming poverty are important factors driving behavior intention.
Low Carbon Travel for the Development of Green Traffic based on Data Envelopment Analysis
ZENG Zhaoxia, LI Mingwei, LIU Daohua
2019, 32(3): 415-420.   doi: 10.3969/j.issn.1003-0972.2019.03.013
[Abstract](221) [PDF 870KB](3)
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In order to clear the positive contribution of the low-carbon transportation to urban green traffic development in our country, the main indicators of low carbon policy to green traffic development are extracted from five aspects:the people, vehicles, roads, transportation infrastructure and transportation environment. Then the equivalent transformation model of linear programming model of C2R is used in data envelopment analysis. Take Guangzhou city as the example to collect the relevant index data from 2005 to 2012, using SPSS and DEAP as the analysis tools to deal with the input and output of low-carbon transportation statistics data. The results of contribution rate show that, with the increase of energy tension and private motor vehicles, the development of public transport enterprise has become the first thing to the urban green traffic development.
Gold Element Fractal Characteristics and Geological Significance of Xiaojiashan Gold Deposit
ZHANG Chenguang, ZHA Daohan, LIU Minghua, ZHOU Hongsheng, SHI Xingjun, YAN Yutong, HUANG Kun
2019, 32(3): 421-425.   doi: 10.3969/j.issn.1003-0972.2019.03.014
[Abstract](408) [PDF 1179KB](1)
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Xiaojiashan gold deposit is located in Qin-hang metallogenic belt in Hunan provice. The orefield has good metallogenetic conditions. But the multistage metallogenic characteristics of the deposit restrict the exploration in the area. Its gold grade and resource were analyzed using the fractal theory, and the relationship between fractal features and gold enrichment and mineralization process was revealed. It has an important guiding significance to ore prospecting to depth and in surroundings of mines.The results showed that the distribution histogram of gold grade indicates that the mineralization process has the characteristics of multistage mineralization superposition. The gold grade has a double fractal structure and fractal dimension, corresponding to the early ore-preenriched quartz-pyrite stage, the main ore-forming quartz-sulfide stage, late quartz-ferrodolomite stage did not contribute to the mineralization, Which reflects the inhomogeneity of mineralization. There are multiple fractals in different sections of the resource quantity, and the fractal dimension value is less than 1, which indicated that the reserves scale of the deposit varies greatly and the distribution was relatively dispersed. The deposit has good prospecting potential.
Temporal Changes of Air Quality in the Central City of Xinyang
YU Guozhong, SHI Huan, WANG Shixiang, ZOU Fajun, ZHAO Chengmei
2019, 32(3): 426-430.   doi: 10.3969/j.issn.1003-0972.2019.03.015
[Abstract](452) [PDF 946KB](6)
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Based on "Technical Regulation on Ambient Air Quality Index (on trial)" and the daily air quality index (AQI) from 2015 to 2017 in the central city of Xinyang of Henan province, China, the monthly arithmetic mean values of AQI per year were calculated, by which the temporal changes of air quality of the city were investigated. The results showed that:the air quality of this city in the studied period had been gradually improved year by year and showed markedly seasonal variations, and each summer had better air quality, and each winter had more air pollution days than other seasons that made it a light pollution season, and the air quality in each spring or autumn was oscillated between better and light pollution grade. Meteorological conditions played an important role in air quality changes of this city, especially the weather conditions of cloudy, overcast sky, drizzle, flurry, sleet, the wind from calm to light breeze and with no sustained direction, in particularly north and northerly wind in each winter, and air pollution could be easily taken place. The city's landform was an obstacle to air diffusion. Therefore, it was very important for this city to focus on the influences of weather and season changes as well as the role of urban planning and designing on air pollution control.
Interaction Effects Between Characteristic Biochemical Components of Tea Plants and Apolygus Lucorum (Meyer-Dür)
YANG Chun, LI Shuai, CHEN Zhengwu, QIAO Dahe, CHEN Juan, MENG Zehong
2019, 32(3): 431-436.   doi: 10.3969/j.issn.1003-0972.2019.03.016
[Abstract](249) [PDF 431KB](3)
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The interaction effects between characteristic biochemical components of tea plant and Apolygus lucorum(Meyer-Dür) was explored, HPLC and UV-Vis were useded to analysis tea biochemical substances in healthy tea leaves and A. lucorum damaged tea leaves. The correlation coefficient between A. lucorum damages index and tea biochemical substances were analysised, the change of tea biochemical components after feeded by A. lucorum were also analysized. The results indicate that the content of caffeine and gallic acid were significantly positively correlated with the tea tree resistant to A. lucorum, while the free amino acids and EGC played the opposite role. Caffeine increased remarkably after damaged by A. lucorum. However, gallic acid dropped off remarkably. Caffeine is the key biochemical component of tea plant to resistance A. lucorum. The lightest damaged tea cultivars TX0310 contains the richest caffeine, and also gained the most after damaged by A. lucorum.
The Inhibitory Effect of EGCG on Breast Cancer Stem Cell Migration and Self-renewal Properties in 3D Culture System
CHEN Lei, LI Kaiming, MA Huijing, WANG Fang, ZENG Xiansi, SONG Xinqiang
2019, 32(3): 437-442.   doi: 10.3969/j.issn.1003-0972.2019.03.017
[Abstract](215) [PDF 811KB](1)
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The pharmacological effects of (-)-epigallocatechin-3-gallate (EGCG) on BCSCs were investigated in 3D culture system. The transcription level of epithelial-mesenchymal transition (EMT) associated genes were significantly downregulated by EGCG, resulting in the inhibition of BCSC migration including the reduction of cell number through 80 μmol/L pore and the attenuation of scratch repair capacity. In addition, the self-renewal capabilities including the expression level of stem cell marker genes and the clone formation capacity were also inhibited in cells cultured in 3D by EGCG. The proportion of stem cell population as detected by flow cytometry with CD24-/low phenotype was also reduced by 80 μmol/L EGCG. Overall, the migration and self-renewal properties of BCSCs were significantly inhibited by EGCG in cancer cells cultured in 3D.
Preparation and H2S Sensing Properties of rGO/Ce-doped SnO2 Nanofibers
WANG Xinchang, GAO Huiran, WANG Yinghua, GUO Menghui, XU Tingting, WANG Yumeng, JIA Jianfeng
2019, 32(3): 443-448.   doi: 10.3969/j.issn.1003-0972.2019.03.018
[Abstract](406) [PDF 1430KB](3)
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The reduced graphene oxide(rGO)/SnO2 nanofibers were prepared via a simple electrospinning method.The effects of Ce doping and doping amount on the microstructure and sensing properties of rGO/SnO2 nanofibers were studied. The morphology and structure of thenanofibers were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and Raman spectroscopy. It was found that Ce doping did not change the morphology and crystal structures of the nanofibers.Gas sensing results showed that different Ce doping could improve the sensitivity of rGO/SnO2 nanofibers to H2S. The composite had the best gas sensitivity to H2S when the Ce doping mole fraction was 3%, at 75℃. The sensitivity of 5 μL/L H2S gas was up to 300, and the selectivity and response recovery performance were also significantly improved.
Fabrication and Characterization of High Strength PNIPAm/Clay Nanocomposite Hydrogels
LIU Yanxia, ZHOU Lili, FENG Xianqi
2019, 32(3): 449-452.   doi: 10.3969/j.issn.1003-0972.2019.03.019
[Abstract](400) [PDF 1370KB](5)
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A kind of novel high strength PNIPAM/Clay nanocomposite hydrogel with superior thermo-responsive nature was successfully prepared using in-situ polymerization method. The results of analysis on the structure of hydrogels using FT-IR spectra, scanning electronic microscopy, and transmittance electronic microscopy technologies indicated that the clay platelets were uniformly dispersed into the polymer matrix based on the hydrogen bond interactions among the clay platelets and polymer chains, which facilitated the formation of uniform internal interpenetrating porous network structure. The results of differential scanning calorimetry illustrated that the incorporation of clay into the polymer matrix would not significantly reduce the sensitiveness of thermo-responsive performance of hydrogels, and the study of swelling kinetics demonstrated that the clearly de-swelled behavior occurred when the hydrogels were immersed into the water at 35℃. The mechanical strength of hydrogels could be extensively enhanced from the incorporation of nano-clay platelets.
Characterization of Silver Nanoparticles Biosynthesized using Crude Polysaccharides of Rubus idaeus and Their Antioxidant Activities
QIN Yin, GOU Qin, XIONG Yinru, ZHANG Qunying, LUO Jiahao, WANG Kainan
2019, 32(3): 453-458.   doi: 10.3969/j.issn.1003-0972.2019.03.020
[Abstract](214) [PDF 1353KB](3)
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Silver nanoparticles (PAgNPs) were green synthesized using crude polysaccharides from Rubus idaeus.extracts and AgNO3 solution. The obtained PAgNPs were characterized by UV-Vis absorption spectrum,scanning electron microscopy (TEM) and X-ray diffraction(XRD). Also, the antioxidant properties of the obtained PAgNPs were assessed in vitro, using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azinobis(3-ethylbenzthiazino-6-sulphonic acid) (ABTS) radical cation decolorization test. The result indicates that the obtained PAgNPs regular spheres with an average size of 20~32 nm and a maximum absorbance at 435 nm. Moreover, PAgNPs exhibited a high radical scavenging activity for DPPH and ABTS+, half radical scavenging activities(IC50) of 64.38mg/L and 75.86mg/L, respectively.
Effects of Surfactants on the CoSb3 Nanopodwers and Amorphization of the Synthesized Nanopodwers
WU Fang, WANG Wei
2019, 32(3): 459-464.   doi: 10.3969/j.issn.1003-0972.2019.03.021
[Abstract](440) [PDF 1485KB](2)
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The CoSb3 nanopodwers were synthesized by the hydrothermal method using different surfactants which were Cetyltrimethyl Ammonium Bromide (CTAB), Ethylene Diamine Tetraacetic Acid (EDTA), sodium dodecyl benzene sulfonate (SDBS) and Polyvinyl Pyrrolidone (PVP). The phase structure and micro-topography of the nanopowders were investigated by X-ray diffractometer (XRD) and a fileld-emission scanning electron microscopy (FESEM). The result showed that different surfactants had significant influence on the morphologies of CoSb3 nanopodwers. Laser rapid quenching method was used to deal with CoSb3 nanopowders that synthesized by the hydrothermal method in order to achieve partial amorphization of the CoSb3.The amorphous conditions of CoSb3 were investigated by the XRD. The results showed that (1) with the increase of the scanning number, the amorphous level of CoSb3 raised; (2) Increasing the scanning speed properly could be helpful to increase the amorphous level of CoSb3.
Preparation of Aupramolecular Self-assembly System Based on Tetraphenylethylene Derivative
CAO Xinhua, DING Qianqian, LI Yiran
2019, 32(3): 465-468.   doi: 10.3969/j.issn.1003-0972.2019.03.022
[Abstract](405) [PDF 970KB](3)
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A new gelator TP based on tetraphenylethylene derivative was designed and synthesized which could form an organogel in 1, 4-dioxane. The self-assembly process of TP was characterized by UV-Vis absorption spectroscopy, fluorescence emission spectra, Fourier transform infrared spectroscopy, scanning electron microscopy and water contact angle. The experiment results showed that a fibers structure obtained in the self-assembly process had some hydrophobility with the contact angle of 136°. The hydrogen bond and van der Waals force were the main driving force for the gel formation.
Efficient Conversion of Biomass-Derived Xylose into Furfural in Ionic Liquids
ZHAO Geng, LIU Ming, XIA Xinkui, LIU Peifang, ZHANG Zongwen, LI Li, BUREN Bayin
2019, 32(3): 469-472.   doi: 10.3969/j.issn.1003-0972.2019.03.023
[Abstract](457) [PDF 574KB](4)
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In the ionic liquids, AlCl3·6H2O was found to be an effective catalyst for the dehydration of xylose. The optimum furfural yield of 76.6% was obtained from xylose under the following reaction conditions:2 g 1-butyl-3-methylimidazolium chloride ([BMIM]Cl), 0.5 mmol AlCl3·6H2O, 5% xylose, at 160℃ for 10 min. These catalytic system consisting of [BMIM]Cl and AlCl3·6H2O could be reused and demonstrated stable activity after five successive runs.
Power Attenuation Analysis of Monocrystalline Modules at the End of Their Service Life
HUANG Jing, LIU Jiangfeng, DONG Xian, YU Zhen, ZHAO Zhiqiang, LU Xiaoman
2019, 32(3): 473-477.   doi: 10.3969/j.issn.1003-0972.2019.03.024
[Abstract](229) [PDF 1222KB](3)
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A batch of monocrystalline modules that have been in service for 20 years in China, were selected to study the power attenuation at the end of their service life. For 132 pieces of monocrystalline module SM55 produced by Siemens Solar in 1996, EL and power related tests were carried out. The average power attenuation was 26.7% and annual average attenuation rate is 1.54%. A simple linear fitting function was used to fit the attenuation of the power with the attenuation of the current and the attenuation of the fill factor. It was found that the power reduction was mainly due to the reduction of the fill factor. Study and analyze the distribution of cracks and fragments in the component cell, and find that cracks and fragments were not the main factors causing component power attenuation. Combined with the environmental conditions in which the components were previously serviced, it was analyzed that the component power attenuation was mainly due to the increase in series resistance.
Application of the Mesh Method on the Mechanism of Absorbing Materials at the Oblique Incidence
HAN Haisheng, MA Jia, ZHANG Haifeng, PEI Weiwei
2019, 32(3): 478-481.   doi: 10.3969/j.issn.1003-0972.2019.03.025
[Abstract](220) [PDF 878KB](1)
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Using the plane wave reflection coefficient formula and transmission line theory of electromagnetic wave, the single layer absorbing material reflection coefficient formula of electromagnetic parameters were given when electromagnetic wave is the oblique incidence. At the meanwhile, the group discussion and matching design with the grid method were carried out to discuss the relationship among the material, thickness, frequency and the reflectivity. The result of research shows that, for the appearance design of low-frequency materials, the thickness gradient design should be adopted according to the strong absorption characteristics at different frequency points.
Research on Warehouse Location of Stereo Garage Based on Beam Search
LI Jianguo, ZHANG Haifei, LI Bowen
2019, 32(3): 482-486.   doi: 10.3969/j.issn.1003-0972.2019.03.026
[Abstract](229) [PDF 861KB](3)
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In order to shorten the running time of the stacker in the stacking garage and the waiting time of the customer, and to improve the efficiency of the stereo garage, a beam search algorithm is proposed to optimize the running path of the stacker. Through the analysis of the physical running stereo garage, the mathematical model of the stereo garage waiting in line is established. Combined with the actual garage location layout, the stacker running distance, average customer waiting time and average queuing length are used as the indicators to analyze and compare the impact of different location layout methods on the overall operating efficiency under a certain location capacity. MATLAB is used to write simulation program, and the operating indicators are compared under the nearest access principle. The results show that under the layout of 4 floors and 6 columns, the operation indexes of the stereo garage are the lowest, and using beam search to select the optimal location is about 50% shorter than the nearest storage run distance, and the average customer wait time and average waiting queue length are shortened by about 31% and 76%. Therefore, beam search has a good effect when selecting a reasonable location layout for a stereo garage.
Experimental Study on Impact Mechanical Properties of RC Beams Replaced by Stainless Steel Bars with Constant Cross Section
ZHOU Xiwu, ZHANG Runcheng, ZHANG Guoxue, WANG Xiangyu
2019, 32(3): 487-491.   doi: 10.3969/j.issn.1003-0972.2019.03.027
[Abstract](405) [PDF 924KB](3)
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Stainless steel bars of equal cross-section is used to replace steel bars in ordinary reinforced concrete beams to solve corrosion problems of steel bars in marine environment. The vertical impact test of six reinforced concrete beams was carried out by using the advanced impact testing system of ultra-high heavy weight drop hammer in China. The impact forces during the impact process, the displacement and strain of the measuring points of the specimens were collected and analyzed. The results show that:(1) when the reinforcement ratio is small (0.21%~0.58%), the stiffness and elastic recovery ability of the beam can be improved effectively after the replacement of the same section, and the deformation of the structure can be reduced. Stainless steel bars can be used to replace common steel bars to solve the corrosion problem. (2)when the reinforcement ratio is higher (1.04%~2.20%), the ductility of stainless steel bar with equal cross-section is worse than that of ordinary steel bar, especially when the impact energy is high, and the brittleness becomes more obvious.
Experimental Study on Compressive Stress-strain Relationship of Alkali-activated Slag Concrete
YUAN Xiaohui, WANG Shige, LI Yongqiang, YAN Qifang
2019, 32(3): 492-497.   doi: 10.3969/j.issn.1003-0972.2019.03.028
[Abstract](219) [PDF 2617KB](3)
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Standard specimen of uniaxial compression concrete prism and concrete filled stell tube(CFST) specimen were made to investigate the alkali-activated slag concrete(AASC) stress-strain relationship by the testing of uniaxial compression and steel tube constraints conditions. The test results show that the relationship between the cube strength and the prismatic strength can still be expressed by the present standard,and the fitted stress-strain relationship curve with the dimensionless two stage stress-strain relationship model is in good agreement with the test curve under uniaxial compression conditions. The ultimate strength and strain of AASC under steel tube constraints condition are significantly increased than those under uniaxial condition, which indicates that the steel tube confinement can improve the strength and toughness of core concrete, and the fitted stress-strain relationship curve with the stress-strain relationship model of the existing steel tube confined core concrete is in good agreement with the test curve. The results show that the existing stress-strain relation model of ordinary concrete is still applicable to AASC under uniaxial compression and steel tube constraints condition.
Roof Movement and Strata Behavior Features of Mining the Remaining Resources
MA Wenqiang
2019, 32(3): 498-504.   doi: 10.3969/j.issn.1003-0972.2019.03.029
[Abstract](226) [PDF 4022KB](1)
Abstract:
To analyze the movement rule and pressure behavior of regenerated roof when mining the remaining lower slice of oil shale, on the background of downward mining oil shale slices in Beizao coal mine, combined with the regenerated roof model built in preliminary work which has cataclastic structure and zoning features, a similar material model of regenerated roof was constructed through improving the traditional material ratio. The characteristics of roof movement, abutment pressure distribution and support stress were studied. The results indicate that the falling rocks of regenerated roof has small crushing expansion coefficient and better compaction. Under situation of the same mining height of the upper and lower slices, both the influence sphere and peak value of lower slice are less than upper slice, which account for 38% and 51% of the upper slice mining, respectively. The support stress of lower slice accounts for 91.6% of upper slice. After the mining of lower slice, both the irregular and regular caving zone height of regenerated roof increase treble over the upper slice mining, and fissure zone height increases about 1.6 times. The results provide some scientific proof for mining design and selection of hydraulic support in similar conditions.
Influence of Dewatering of Foundation Pit on Beneath Subway Shield Tunnel
ZHANG Ming, LIANG Tianyi
2019, 32(3): 505-510.   doi: 10.3969/j.issn.1003-0972.2019.03.030
[Abstract](228) [PDF 1109KB](3)
Abstract:
Combined with a complex environment condition of foundation pit engineering with an apartment, considering the condition including shield tunnel of metro beneath foundation pit, a simplified big well method is firstly used to calculate the hydraulic gradient curve of outer stratum of foundation pit under the dewatering condition of curtain failure(condition one), and two-dimensional finite element method is used to calculate the hydraulic gradient curve of outer stratum of foundation pit under the dewatering condition of effective curtain(condition two). Then the additional settlement of subway shield tunnel caused by dewatering of foundation pit is calculated by the layered summation method, and the influence of dewatering of foundation pit on underground subway is analyzed. The results show that:(1) Considering two dewatering conditions including the failure and effective of water proof curtain, the drawdown of the central axis on the right line of subway shield tunnel are 4.2 m and 1.5 m, respectively; (2) Considering two dewatering conditions including the failure and effective of water proof curtain, the maximum settlement of the central axis on the right line of subway shield tunnel are -2.83 mm and -1.3 mm, respectively, which meets the safety operation requirements of rail traffic.
Research Progress in Plant Cold Resistance Mechanism
ZHOU Qiying, HAN Yuehua, PAN Juanjuan, YUAN Hongyu, LI Xianwen, QIN Muxue, PENG Bo, ZHU Yue
2019, 32(3): 511-516.   doi: 10.3969/j.issn.1003-0972.2019.03.031
[Abstract](246) [PDF 424KB](6)
Abstract:
Low temperature damage is one of the main stress factors affecting crop distribution, yield and quality, and research in plant cold resistance mechanism is an active and fast developing field. Here, research on plant cold resistance mechanism was reviewed from four aspects:the physiological and biochemical basis of plant cold resistance, the perception of low temperature signal, the transmission of low temperature signal in plants, and the expression regulation of plant cold responsive genes. Additionally, the prospects of the application of research on plant cold resistance inagricultural production was discussed.
2019, 32(3): 517-517.  
[Abstract](266) [PDF 334KB](8)
Abstract:
2019, 32(3): 518-518.  
[Abstract](250) [PDF 210KB](3)
Abstract:
Journal introduction

Started:in 1981,Quarterly

Administrative Department: Xinyang Normal University

Sponsor:Xinyang Normal University

Editor & Publisher:the Editorial Department of Journal of Xinyang Normal University

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