Bulgarian Chemical Communications, Volume 49, Special Issue-K2, 2017
 
Contents:
   
1

Screening of an attenuated strain of Fusarium oxysporum f. sp. cucumerinum using rhizosphere soil treated with ethanol extract of parsley (Apium graveolens)
Original Research Article
Pages 5 – 10
Q. Lijin, S. Zhiyong, G. Cheng, Q. Cheng, Y. Xingfu
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Abstract
In the present study, an ethanol extract of parsley (Apium graveolens) fresh rhizosphere soil was supplemented to PDA plates for successive culturing of Fusarium oxysporum f. sp. cucumerinum, to screen an attenuated strain of F. oxysporum f. sp. cucumerinum. The results revealed that 50 mg·mL-1 ethanol extract of parsley fresh rhizosphere soil had allelopathic inhibitory effect on the first to fifth generation of F. oxysporum f. sp. cucumerinum. The diameter of colonies displayed significant difference between ethanol extract-treated and control 48 and 144 h after inoculation (P <0.05). F. oxysporum f. sp. cucumerinum from the first to fifth generation was attenuated in virulence by the ethanol extract of parsley rhizosphere soil, and the virulence of F. oxysporum f. sp. cucumerinum decreased with the increase in generation number. As a result, an attenuated strain of F. oxysporum f. sp. cucumerinum with only 6.7% virulence was screened out from the fifth generation.

   
2

Impact of nitrogen addition on plant litter decomposition in a sheepgrass meadow steppe
Original Research Article
Pages 11 – 13
C. Shang, Q. Zhang, H.L. Zhang, J.K. Li, H.Y. Liu, J.L. Liu, R.F. Zhu, X.L. Kong, J.S. Chen
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Abstract
In order to examine the effect of species (S) and nitrogen (N) on litter decomposition rate and the cumulative CO2 emissions, litter from three species and soil samples subjected to different N-addition treatments (CK, LD, MD, HD) were collected from a sheepgrass (Leymus chinensis Tzvel) meadow steppe. We found litter of L. chinensis had higher initial nitrogen content and lower carbon to nitrogen ratios and decomposed faster than that of A. hirta while each species decomposing in isolation. Moreover, N addition significantly enhanced litter decomposition rate of each species. Estimated litter decay rate constant (k) under N-free treatments was significantly lower than expected based on N-added soils results, while the k was affected by nitrogen addition and increased by amount of nitrogen addition, indicating exogenous N additions could positive effects, and the positive effects of N additions on litter decomposition could influence litter decomposition and, therefore, Carbon as well as nutrient cycling in sheepgrass meadow steppe.

   
3

Simultaneous saccharification and co-fermentation of steam-exploded poplar wood to ethanol with Escherichia coli KO11
Original Research Article
Pages 14 – 19
B. L. Ai, Z. W. Sheng, Q. Y.Wang, L. L. Zheng, X. Y. Zheng, Y. Q.Wang
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Abstract
Steam explosion pretreatment is a promising method for the preparation of lignocellulosic biomass for biofuels production. Steam explosion was performed to assess the effectiveness of pretreating poplar wood for ethanol production. Maintaining steam pressure at 4 MPa for 10 min, 66.8% of hemicellulose and 5.3% of cellulose were hydrolyzed. The scanning electron microscopy observation, FT-IR spectroscopy analysis and X-ray diffraction analysis showed that hydrolysis of hemicellulose and modification of cellulose and lignin structures improved the accessibility of cellulose to hydrolytic enzymes. Cellulase production by Trichoderma reesei RUT C-30 was initiated with inocula prepared by different methods. It was found that the composition of pre-culture medium and inoculum age have minimal or no impact on cellulase production. Using the steam-exploded poplar wood as feedstock with cellulase loading of 20 FPIU g−1 substrate, ethanol production by gene-engineered Escherichia coli KO11 reached 3.6 g L-1, corresponding to 51.4% of the maximum theoretical yield based on glucan remaining in the input substrate. The ethanol yield was limited by the low solid content of steam-exploded residue, and inhibited by the inhibitors released in the pretreatment process. So the steam explosion process needs to be improved for lower water content and less inhibitors, and detoxification is necessary to achieve a good fermentability of pretreated poplar wood to ethanol.

   
4

Hydraulic design and numerical investigation of twin-screw hydraulic turbine for high pressure power recovery
Original Research Article
Pages 20 – 25
Q.Li, S. H. Liu, X. P. Jiang, L. Zhou, W. Li
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Abstract
As a novel type of energy recovery device based on the reverse operation principle of screw pump, the twin-screw turbines (TSHT) are widely used in high-efficiency sea water reverse osmosis systems. It is important to investigate the performance and internal flow patterns of TSHT. The research presents the hydraulic design of TSHT and analyzes the general characteristics of the internal flow field and the efficiency performance by numerical simulation and experimental methods. In order to solve the Navier-Stokes equations for three-dimensional unsteady flow, dynamic mesh technique was used in the commercial Computational Fluid Dynamics (CFD) software. Pressure distribution and velocity distribution, as well as efficiency performance of the flow field were studied by the numerical simulation method which was validated by the prototype experiment. The twin-screw hydraulic turbine (TSHT) can be widely used in sea water reverse osmosis systems for power recovery due to its stable performance.

   
5

Effect of environmental regulation on the manufacturing FDI in China: spatial econometric studies
Original Research Article
Pages 26 – 31
W.H. Li, C. Li, W.Ch. Huang, C.J. Dong
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Abstract
Previous studies on the relationship between foreign direct investment (FDI) and environmental regulation have generally not considered the spatial characteristics. This paper applies spatial econometrics to explore whether or not environmental regulation inhibits the inflow of manufacturing FDI to China. Using a dataset across China’s 29 provinces over the period from 2010 to 2015, we examined the spatial autocorrelation pattern about manufacturing FDI. We then used an improved spatial econometric model to explore the effect of environmental regulation on manufacturing FDI, incorporating other determinants of FDI, including the level of economic development, the degree of industrialization and the manufacturing labor cost. Our study reveals that manufacturing FDI exhibits clear spatial autocorrelation and regional agglomeration characteristics. Furthermore, the inhibitory effect of environmental regulation on manufacturing FDI inflow is gradually increasing with the passage of two stages, which confirms the “pollution shelter” hypothesis in China. We also find positive effects of the level of economic development and the industrialization degree on the manufacturing FDI inflow while, as expected, the manufacturing labor cost is found to be negatively correlated with FDI inflow.

   
6

Study on the application of a self-regulating heater for pre-control of concrete curing temperature in winter
Original Research Article
Pages 32 – 37
Liu Lin
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Abstract
As a concentrated high-temperature exothermic material, a self-regulating heater is embedded in the concrete for heating and maintenance in winter, which can greatly improve the short concrete construction period in a severe-cold area. In order to achieve the expected temperature control, adjust the performance of concrete and optimize the design method of heating and curing, a pre-control method of concrete temperature history with the change of hydration degree is established based on the first law of thermodynamics, using the concept of equivalent age, considering the effect of temperature on the hydration reaction and thermal performance of concrete through the expected mechanical strength design. The method was verified by a temperature control test. The results show that the method can effectively control the heating rate of concrete. When the temperature at the design stable phase is 45oC, the temperature at the concrete phase is relatively stable due to the decrease of hydration reaction, slowly decreasing at a rate of 0.11 oC /h and 0.08 oC /h. The temperature at the actual stable phase is in the range of 39.69-45.63 oC, the variation range is 0.12%. The buried heat source can effectively accelerate the hydration reaction, and the hydration degree under the condition of 45 oC for 3 curing days equals to that at 20 oC for 7 curing days.

   
7

Influence of hydraulic flow and clay hydration on pore pressure and collapse pressure of swelling shale
Original Research Article
Pages 38 – 43
H.B. Liu, F. Zhang, Y.F. Meng, G. Li, G.D. Zhang
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Abstract
A modified model for wellbore instability of shale formations is developed by considering the coupled flows of water and ions, crystal hydration and osmotic hydration of clay minerals. Based on the thermodynamic theory, we proposed new models to describe the hydraulic flow of water solutions and chemical diffusion of ions, taking into account the permeability and porosity of formation. Simultaneously, we deduced a new expression for the total stress controlling the clay crystal swelling and osmotic swelling with the energy balance between adjacent clay crystals and the diffuse double layer theory. Theoretical simulation indicates that the effects of clay hydration swelling are related to formation water, drilling fluid and ion salinity, as well as the spacing between adjacent clay crystals, and clay crystal swelling stress is far higher than the osmotic swelling stress between clay particles when the spacing is shorter than 4 nm. Ultimately, based on the modified effective stress laws, considering the mineral distribution in shale formation, pore size and clay hydration, the borehole stability model of physico-chemical coupling effects in shale was developed.

   
8

Mechanical properties and microstructure of hot rolled NM360/Q345R composite interface analysis
Original Research Article
Pages 44 – 47
J.Li, L. Ma, G. Zhao, Q. Huang, X. Yang, M. Cheng
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Abstract
The rolling reduction rate is one of the important factors that affect the bonded reduction rates. The NM360/Q345R composite plates were analyzed by a universal tensile testing machine, OM, SEM and EDS. As the rolling reduction rate increased, both the tensile strength and the elongation increased. When the reduction rates were 30% and 50%, the bonding interface was poor and apparent cracks could be observed after the tensile tests. When the reduction rate reached 70%, no voids or cracks existed, the breaking interface was smooth and neat and the bonding interface formed a common structure. Significant decarbonization of NM360 occurred at the bonding interface. When the reduction rates were 30% and 50%, long strips or black dots of particles appeared near the interface. The black particles were Mn and Si oxides, which could have a negative effect on the bonding interface.

   
9

Effect of additives on thiosulfate leaching of a gold ore
Original Research Article
Pages 48 – 53
S.J. Dai, P.C. Li, Q.Q. Wang, D.W. Feng
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Abstract
The effect of additives on gold leaching was investigated using ammonium thiosulfate or calcium thiosulfate. Thiosulfate stability was evaluated with additive dosage and thiosulfate type, usage, and ageing. The study results showed that ethylene diaminetetraacetic acid (EDTA) at its optimum concentration of 2 mM enhanced gold leaching and slightly improved the stability of gold thiosulfate species in solution while carboxy methyl cellulose (CMC) improved gold leaching, but gold was not stable in solution. There was an optimum CMC dosage, and beyond this, further addition of CMC hindered gold leaching. The surfactant sodium dodecyl sulfate (SDS) sodium dodecyl sulfate (SDS) sodium dodecyl sulfate (SDS) sodium dodecyl sulfate (SDS)sodium dodecyl sulfate (SDS) sodium dodecyl sulfate (SDS) sodium dodecyl sulfate (SDS) sodium dodecyl sulfate (SDS)sodium dodecyl sulfate (SDS) sodium dodecyl sulfate (SDS) sodium dodecyl sulfate (SDS) sodium dodecyl sulfate (SDS) sodium dodecyl sulfate (SDS) had a similar effect to CMC. At an agitation speed of 250 r/min, 100% leach recovery of gold was achieved with 0.03 M fresh ammonium thiosulfate, 2 mM EDTA after 11 h leach. In a resin-in-leach system, full gold recovery was also achievable with sufficient resin after 24 h leach with 0.06 M fresh ammonium thiosulfate and 2 mM EDTA at an agitation speed of 250 r/min.

   
10

Study on the effect of diesel blended with n-butanol on particulate matter state characteristics of a small agricultural diesel engine
Original Research Article
Pages54 –58
L. Chen, Z. Wang, S. Liu
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Abstract
This work studied the effect of diesel blended with n-butanol on particulate matter (PM) state characteristics of a small agricultural diesel engine which revealed the mechanism of n-butanol reducing PM emissions in diesel engine. The microstructure, oxidation characteristics, components and surface functional groups of PM with N5 (5% n-butanol and 95% diesel fuel in quality basis), N10 and diesel fuel were measured. The results indicated that n-butanol/diesel PM displayed cluster structure. With the increase in n-butanol content, the average diameter of PM gradually decreased while aggregation degree increased. Pyrolysis of PM in the air was divided into two stages - soluble organic matter evolution stage and soot combustion stage. With the increase in n-butanol content, the initial combustion temperature of soot decreased, the temperature corresponding to the mass change rate peak of weightlessness with PM dropped, soluble organic matter and soot content in particulate fractions increased, while metal and inorganic salt content decreased. The equivalent peak height ratio (IC-H-IC=C)/IC=C of aliphatic functional C-H on particulate surface increased and its relative content gradually increased.

   
11

Research on acetylation and antioxidant activity of Russula alutacea Fr. water-soluble polysaccharides
Original Research Article
Pages 59 – 63
Y. Zhao, X.N. Li, T. Chen, Q.Y. Tang, Q.P. Duan, B.J. Wang, Q.S. Yang
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Abstract
There is a large amount of alkali-soluble polysaccharides in Russula alutacea Fr., but insolubility in water limits its development. Chemical modification can improve the solubility of natural polysaccharides limiting their activities, and enlarge their application range. Water-soluble polysaccharide was extracted by water and precipitated with alcohol in this study. It was further modified by acetylation, thus improving its water solubility. The scavenging activity of water-soluble polysaccharide, acetylated polysaccharide and vitamin C on the hydroxyl radical (OH•), 2,2-diphenyl-1-picrylhydrazyl (DPPH), superoxide anion(O2-•) was analysed and compared. The results showed that water-soluble polysaccharide, acetylated modified polysaccharide and vitamin C have a strong scavenging effect on O2-• which increases with the increase with mass concentration in the range of 0.34 ~ 1.7 mg/mL of mass concentration. The yield of water-soluble polysaccharide was 1.75%. The mass concentration of acetic acid was 0.63 mg/ml, the degree of substitution (DS) was 0.44%. According to its EC50 value, it can be concluded that the order of OH• scavenging ability was: VC>acetylated polysaccharide>water-soluble polysaccharide; the order of DPPH scavenging ability was: acetylated polysaccharide>VC>water-soluble polysaccharide; the order of O2-• scavenging ability was: VC>acetylated polysaccharide>water-soluble polysaccharide.

   
12

Kinetic analysis of biogas produced from kitchen waste conducted using population growth & first order analytical models
Original Research Article
Pages 64 – 68
L. Feng, T.Y. Gao, S.Y. Gu, W. Kou, P. Gao, X.Y. Dong, M.L. Yu, D.L. Zhang, J.Z. Wang
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Abstract
Sequencing batch anaerobic digestion (AD) of kitchen waste at 37 ºC was studied. The classic population growth equations and the first-order biogas production were used to analyze the characteristics of biogas production in kitchen waste anaerobic digestion process under the condition of initial total solids (TS) = 4, 5, 6 and 7 wt %. Logistic equation was better fitted to the experimental data for kitchen waste of initial TS=7 wt % comparing with the modified Gompertz equation. For kitchen waste (AD) process at other TS concentrations in this research to the Modified Gompertz equation was preferred. No lag phase time appeared in the experiment, k of kitchen waste of initial TS= 4, 5, 6 and 7 wt % were 0.2179, 0.1430, 0.1170, and 0.0954, respectively. The kitchen waste of initial TS=4 wt % gave the highest biogas production, followed by initial TS=6 wt % and initial TS=5 wt %. The kitchen waste of initial TS=7 wt % displayed the worst characteristics of biogas production.

   
13

High-solid hydrolytic kinetic model of kitchen waste anaerobic digestion
Original Research Article
Pages 69 – 73
L. Feng, N. Wang, S.Y. Gu, W. Kou, P. Gao, X.Y. Dong, M.L. Yu, D.L. Zhang, J.Z. Wang
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Abstract
The high-solid kitchen waste fermentation process can be divided into four phases: adaptation (0~13 d), start-up (14~34 d), inhibition (35~72 d), and recovery and stabilization (72~120 d). In dry kitchen waste fermentation, the reaction rate constant k was found to be 0.133 d-1 depending on the hydraulic retention time (HRT), organic loading rate (OLR), and maximum gas production rate of kitchen waste at the different fermentation phases. The formula for the relationship between the cumulative gas production (L) and time (d) was: y = 0.1139x2 - 5.0447x + 77.737. The cumulative gas (L) y and the reaction time relationship (d) x obeyed the corresponding linear relationships in each period.

   
14

Helicopter transient electromagnetic combined waveform transmitting technology for metal exploration
Original Research Article
Pages 74 – 79
B. Guo, Y. M. Zhang, J. L. Zhang, X. H. Wang, J. Z. Ding, J. X. Gao
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Abstract
Aiming at the technical requirements to a Helicopter Transient ElectroMagnetic (HTEM) transmitter for metal ore exploration, a novel multi-pulse transmitter circuit based on LC resonance principle is proposed. Based on the full control characteristics of the IGBT device and the energy four-quadrant operation technology of the bridge circuit, a combined multi-pulse transmission circuit was realized, and precise driving timing was generated by the DSP module. The power control circuit transmits a multi-pulse waveform consisting of half-sine and trapezoidal wave to realize reuse of the same set of circuits. The principle and the circuit design method of multi-pulse emission were discussed in detail. The dynamic process and the circuit parameters of energy conversion in the half-sine and the trapezoidal wave were analysed. A bipolar multi-pulse transmitter prototype circuit with main pulse of 500A and trapezoidal wave of 50A was developed and verified by test experiments. The test results showed that the emission control method proposed in this paper achieves high-pulse current emission and small-pulse emission along the steep edge, the small-pulse edge is linearly turned off and the pulse duration is controllable. The validity of the proposed circuit topology was verified and the capability of HTEM transmitting system was improved.

   
15

Experimental study on permeability improvement of different rank coal samples by acidification
Original Research Article
Pages 80 – 89
M.K. Luo, S. Li, C. J. Fan, Z. H. Yang, H. Z. Yang
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Abstract
In view of the fact that the coal seam is blocked by filling material, the permeability in the coal seam is low. Therefore, a new method was put forward to enhance the permeability of coal seam by acid injection. The permeability increase effect via acid injection in different-rank coal reservoirs was studied. The characteristic changes of surface structure, pore structure, mineral content and permeability of coal samples were analyzed by SEM, ASAP, XRF and permeability measurements. Experimental results showed that: After acidification, the surface crack profile of the coal sample was clearer, the number and width of the cracks increased, the porosity-fracture network connectivity was enhanced, but the dissolution effects of high-rank coal were relatively poor. The specific surface area of coal samples decreased, the pore volume increased, and the changes were mainly concentrated at the pore width of 2~10 nm. Ca, Mg and other mineral content obviously decreased. Acidification did not cause damage to the organic matter of coal. The permeability of coal samples generally increased, the lower the coal rank, the higher were the initial permeability and the carbonate mineral content, the more obvious was the permeability increment. Coal injection technology can effectively improve the pore structure of coal, enhance the diversion capacity, and increase the permeability of coal reservoir, which leads to the improvement of gas drainage rate and gas resource exploitation.

   
16

Comprehensive evaluation and case study of urban underground space development under multiple constraints
Original Research Article
Pages 90 – 97
C.A. Zhou, H. Ren, G. Liu, C. Chen
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Abstract
This paper presents a research on the evaluation and case analysis of urban underground space development under several constrains such as geological, technical and economic factors. To solve the problem of incomplete information, correlation and ambiguity in the multi-restrictive environment factors were comprehensively evaluated. First of all, six main factors which restrict the urban underground space sustainable development were selected; secondly, the degree of the restrictive factors and their frequency were discussed, the restrictive factors which occupied more than 95% were determined by expert advice, the evaluation index was quantified by the Likert scale, the evaluation index system of urban underground space sustainable development and utilization was constructed. Moreover, Analytic Hierarchy Process (AHP) and Fuzzy Comprehensive Evaluation Method (FCE) were used to construct the fuzzy comprehensive evaluation model of multi-level constraints, the weight vector for consistency check was calculated, and the fuzzy evaluation membership matrix was computed. Finally, Jiangbei District, Hechuan District and Qianjiang District in Chongqing City were chosen as representatives of urban function core district, city development district, and southeast ecological reserve district in Chongqing City. The urban underground space sustainable development in the chosen districts was analyzed by the multi-factors fuzzy comprehensive evaluation model, and the evaluation results were verified by multi-level grey assessment. The case study results showed that applying AHP and FCE method for multi-constraint factors comprehensive evaluation of urban underground space sustainable development has high viability and effectiveness for the beneficial exploration and comprehensive evaluation of multi-restrictive environment factors.

   
17

Social network analysis of innovation of industry-university-research cooperation in chemical industry (based on China patent licensing data)
Original Research Article
Pages 98 – 103
H.Y. Yan, X.Z. Bao, Q. He
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Abstract
Industry-university-research cooperation is one of the main ways for an enterprise to gain a competitive advantage. Based on the research perspective of social networks, this paper uses patent licensing announcement in the chemical industry among universities, research institutes and enterprises in 2010-2013 as the data source, and draws a map of innovation network of industry-university-research cooperation in the chemical industry using the software of Pajek and Gephi, and makes an analysis on trend and innovative subject analysis as well as the characteristics of innovation network of industry-university-research cooperation in the chemical industry. The results show that innovation network of industry-university-research cooperation in the chemical industry is a complex network system as a whole with more nodes and uneven distribution, showing scale-free and small-world properties. Chemical enterprises should actively participate in the industry-university-research cooperation and play the role of innovative subject in the industry. They need to establish a stable and effective incentive mechanism for innovation network environment, information and resource sharing, and promote interaction among network actors to enhance innovation ability of all parties.

   
18

Biodegradation of di-n-butyl phthalate ester by newly isolated Raoultella sp. ZJY
Original Research Article
Pages 104 – 108
T. F. Liu, H. Y. Zhang, J. Y. Chu, L. Q. Qiu
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Abstract
A bacterial strain ZJY that could degrade di-n-butyl phthalate was isolated from sludge of river of Hangzhou city, and identified as Raoultella sp. by morphological, physiological characteristics and the analysis of 16S rRNA gene sequence. The results of DBP-degrading characteristics showed that the optimal temperature and pH for dibutyl phthalate biodegradation was 30 °C and 7.0, respectively. The degradation was best fitted by first-order kinetic equation and the half-life was 40.81 h at 418 mg/L dibutyl phthalate of initial concentration. GC-MS analysis of the metabolites revealed that initial step of dibutyl phthalate was degradation was transesterification. To our knowledge, this is the first report on the biodegradation characteristics of DBP by a member of the Raoultella genus.

   
19

Methods for modeling spatial variability of soil organic carbon under different land use in middle reaches of the Heihe river basin, northwestern China
Original Research Article
Pages 109– 114
J.H. Zhang, G.D. Li, C.l. Lu, Y.H. Liu, Y.P. Ding
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Abstract
The aim of this paper is to identify the influence of land uses on soil organic carbon (SOC) distribution in the middle of Heihe, China. Geostatistical methods including ordinary kriging (OK), spline (SPLIN), inverse distance weight (IDW) and local polynomial interpolation (LP) were compared. It is noteworthy that OK engenders smaller prediction errors than SPLIN, IDW, and LP. We selected the OK method to estimate SOC distribution. Results show that spatial distribution of SOC has an obvious gradual decreasing trend from high to low sections at different layers in the depth of the 100 cm soil profile. Most notable is that SOC content of cultivated land is higher than that of desert, sandlot, saline-alkali and naked fields. From a spatial perspective, paddy fields with a long history of cultivation are distributed on the two sides of Heihe river, while land with a shorter history of cultivation is located at a greater distance from the river. Land use change will increase or decrease SOC content. The extension of cultivated land with desert, naked land, sandlot, saline-alkali fields and middle density grassland with low SOC content will enhance the content of SOC in soil profile by a carbon fixation process, although sandy desertification is a reverse process. The results show that cultivation is an important process of increasing SOC content.

   
20

Characterization of a glycoprotein from the silk of caddisfly Stenopsyche marmorata
Original Research Article
Pages115 – 120
Q. Lin, H. Wang, H. Chen, Y. Peng, B. Kwan, M. Nakagaki, Y. Wang
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Abstract
By sequencing the N-termini of the luminal proteins and screening the silk gland cDNA library of the caddisfly Stenopsyche marmorata (S. marmorata), a major silk component (Smsp-12k) which proved to be a glycoprotein, was identified in this suborder. The primary structure of Smsp-12k consists of three degenerate repeats with Gly (29.7%), Trp (18.7%) and Ser (13.2%) present as the most abundant amino acids. The SXSXSXSX and GGX motifs were repeatedly found in Smsp-12k and are also present in the repetitive region of the heavy chain fibroin (H-fibroin) of S. marmorata. The SXSXSXSX and GGX motifs confer toughness and elasticity to the caddisfly silk, respectively. The abundant expression and structural resemblance of Smsp-12k to the repetitive region of H-fibroin indicates that this protein may play an important role in contributing to the physical properties of the aqueous silk.

   
21

Effect of maize irrigation on water use efficiency in the Semiarid region of Northeast China
Original Research Article
Pages 121 – 127
H.X. Zhao, S.F. Bian, L.C. Wang, X.Q. Fang, G.B. Tan, L.H. Zhang, W.P. Yan, N. Sun, X.M. Meng
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Abstract
In order to popularize and apply technology of the corn regulated deficit irrigation in Northeast Semi-arid Region and achieve efficient use of water resources, the test was carried out to deal with different degrees of water deficit processing of corn in different growth stage, and studied the effects of Regulated Deficit Irrigation on maize’s water consumption, yield and water use efficiency (WUE). The results showed that: in terms of the regulated deficit irrigation of each growth stage, the heavy drought will affect the yield greatly during tasseling periods, while the water deficit had little effect on the yield in seedling stage. It showed a downward opening parabola relationship between the yield and water consumption, and if the maize is short of water in the jointing stage, the yield would be significantly decreased. It needs to be dealt with water deficit of maize appropriately, and the best irrigation treatment mode is the moderate water deficit in the seedling stage (the upper limit of water control was 60%).

   
22

Optimization of pepsin-assisted extraction of polysaccharides from Cynomorium songaricum
Original Research Article
Pages 128 – 133
H. Fan, Y. Su, L. Wang, G. Chen
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Abstract
In this paper, the pepsin-assisted extraction of Cynomorium songaricum polysaccharides was investigated. The study comprised a single factor experiment design and an optimization response surface methodology using Box-Behnken design providing the optimal extraction conditions as pH of 1.5, liquid-to-solid ratio of 108:1, and proteolysis temperature of 40 °C. Under these conditions, the highest C. songaricum polysaccharides yield reached 23.63 ± 0.21%, which represented an increase of 233% compared to the conventional hot-water extraction. Their structures were determined via chemical analysis, ultraviolet spectra, Fourier-transform infrared spectra, scanning electron microscopy, and atomic force microscopy. These findings may provide a theoretical basis for further systematic research and utilization of C. songaricum polysaccharides resources.

   
23

Research on health assessment of main forest vegetation in Kuankuoshui nature reserve
Original Research Article
Pages 134 – 139
C.W. Zhou, L.B. Yan , L.F. Yu, C.H. Zhong, G.P.Chen, C. Zhou, F.J. Pi
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Abstract
The main forest vegetation health evaluation studies in nature reserves provide scientific basis for their operation and management and are of significance for the sustainable development of forest vegetation in nature reserves and the further improvement of the nature reserves construction. This study of the Kuankuoshui national nature reserve of Suiyang county as the research object, combined with Kuankuoshui nature reserve forest resources "second subcompartment survey" in 2031 subcompartments samples and 80 000 data, applying sensitivity analysis, etc. to screen indicators, adopting an analytical hierarchy process to determine the weight of each index, set up the main forest vegetation health evaluation model of the broad water nature reserve. To assess the broad water nature reserve, evaluation analysis of the main forest vegetation health was performed. The main results were as follows: The nature reserve is in a relatively healthy grade as a whole,the forest subcompartments evaluated as unhealthy are composed by ≥25° slope farmland, shrub wood, unformed man-made forest, barren hills and wasteland suited for forestry.

   
24

Study on functional division optimizing of Kuankuoshui national nature reserve based on resistance surface analysis
Original Research Article
Pages 140 – 143
L.B Yan, L.F. Yu, C.W Zhou, R. Yang
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Abstract
Functional division of nature reserve is the region set for the protected object. For optimizing and adjusting it, we selected Kuankuoshui national nature reserve as research area. This research utilized 5 ecological sources as research objects, which included 4 types of animals (Phasianidae, Cervidae, Felidae and Primate) and Fagus lucida woods, and the used resistance factors containing altitude, slope, landscape type and rock bare rate defined the distribution pattern of the resistance surface. The complex strategic points were identified by combining the statistics and superposition of the ecological corridors. The results showed that the resistance surface model gives excellent simulation of the potential biodistribution; classical function zoning may protect the ecological source and strategic points at saddle points except for strategic points at intersections, multiple strategic points at intersections and multiple ecological corridors. On the basis of the research results suggestions are put forward for the functional division adjustment, three-dimensional ecological corridor construction measures and management measures on time.

   
25

Research on the ecology spatial pattern of basic farmland guided by the concept of “negative planning”
Original Research Article
Pages 144 – 151
X.Lan, Z. Q. Wang, C. Wei, L. G. Zhang
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Abstract
After the 19th National Congress of the Communist Party of China had been launched successfully, the Chinese government showed confidence by improving the ecological environment of the whole country in changing the traditional planning method which considers the social and economic benefits rather than the ecological one. In this paper, the simulation experiment tries to delimit an area of ecological infrastructure with the guidance of the “security pattern” and “negative planning” concept which has a more favorable index of ecological environment than the traditional way in the spatial pattern planning of basic farmland. The results show that the new planning provides more high-quality and less fragmentary cultivated land than the traditional one, and the cultivated land is more adaptable in biodiversity and producing activity, which is in line with the development of environmental policies of the Chinese government and the global sustainable development.

   
26

Efficiency analysis of cross-season high-temperature energy storing in cold areas based on FLUENT simulation
Original Research Article
Pages 152 – 155
K. R. Ma, M. H. Cui, Ch. M. Ni, R. J. Yu, X. D. Xian
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Abstract
In this paper, by applying FLUENT simulation, a heat-storing and heat-removing system in cold areas was simulated, based on the interaction between the solar energy and the buried pipes. In spring, summer, and autumn, the soil is heated by the hot water produced from the solar energy, so the temperature of the soil is accordingly risen. This is the heat-storing stage. In winter, the cold water within the buried pipes is heated by the high-temperature soil, which can provide heat for the building. This is the heat-removing stage. According to this simulation process, the geometrical and mathematical models were established, the data when the system reaches balance were analyzed, the optimal distance for placing the buried pipes was obtained, and reference for actual projects was eventually provided.

   
27

A study method of risk evaluation for children’s toys
Original Research Article
Pages 156 – 161
G.Z. Huang, A.W. Zhou, S.H. Sun, N. Wang
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Abstract
China is an important toy production and export country in the world. The injury incidents caused by Children's toys have become increasingly prominent, and the recall of toys also led to a large number of economic losses. Therefore, in this paper, the fuzzy comprehensive evaluation method is proposed for the children’s toys risk evaluation. Firstly, the ETA method is used to determine the index and establish the index system of risk evaluation for children’s toys. To determine the index weight, AHP method is adopted to calculate the weight of each index. Then make the fuzzy comprehensive evaluation model for the risk evaluation of children’s toys. Finally, the feasibility and effectiveness of method were illustrated by an example. Result shows that it provides a new perspective and tool for the risk evaluation of children’s toys.

   
28

Research of Morinda officinalis How’s oligosaccharide extraction and antidepressant effects
Original Research Article
Pages 162 – 167
X.J. Li, S.Y. Ma, D. Cheng, H.S. Chang, L.L. Li, Y. Lu
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Abstract
Morinda officinalis How, as a traditional Chinese medicine aiming at nourishing kidney yang, not only can remove wind-dampness effects and strengthen muscles and bones, but, according to modern research, has also antidepression effect, enhances immunity and other functions. These functions are related to its complex chemical composition. Morinda officinalis How’s polysaccharide has been widely used in food, health care products and other fields. At present, in the field of medicine, oligosaccharides from Morinda officinalis How gain more attention. A number of experiments show that Morinda officinalis How’s oligosaccharides have a good antidepressant effect with less toxic side effects compared with Western medicines. However, the physical and chemical properties of oligosaccharide monomers are similar, so oligosaccharide monomers are hard to be separated and detected. This paper organized literature related to the chemical composition and pharmacological effects of Morinda officinalis How at home and abroad, and summarized the extraction method and antidepressant effect of Morinda officinalis How’s oligosaccharides. In addition, it provided scientific basis for further development of Morinda officinalis How medicine, and tried to improve the utilization of Morinda officinalis How.

   
29

Bibliometric analysis of integrated complementary medicine research articles included in Science Citation Index
Original Research Article
Pages 168 – 172
J. Zhu, X. Zhai, Y. Chang, J. Liu, X. Sun, K. Liu, F. Guo, Y. Huang, X. Li, X. Cao, B. Wen, X. Xu, Z. Guo, X. Ma
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Abstract
More and more new concepts and methods are surfacing thanks to integrated complementary medicine research. As many laws and new discoveries have been covered in the sea of existing literature, understanding research progress and following its direction has become difficult for researchers. This study investigates the global development of integrated complementary medicine research over the past ten years through bibliometric analysis to provide reference to researchers for future work. Searched and selected were articles in 22 integrated complementary medicine journals published globally in the Web of Science database. Analysis of the articles was based on changes of publication years, geographical distribution, research institutes, research fields and so on with multiple bibliometric analysis methods. Generally, the total amount of integrated complementary medicine research articles has increased. However, there was a slight decrease in the last two years. Research in China, US and South Korea has taken the dominant position. Integrated complementary medicine is the inevitable trend of the development of Chinese medicine and even world medicine. Traditional Chinese medicine should take in achievements of modern technology to make breakthroughs. Although research in the last two years declined compared with the peak time of 2013, integrated complementary medicine research will still flourish. There will be more and more research institutes and researchers involved in the near future.

   
30

Research on plasma metabolomics of hypertensive rats with liver–fire hyperactivity syndrome
Original Research Article
Pages 173 – 177
J. Zhu, J. Liu,X. Li,Zh. Li,X. Zhai, T. Wang, X. Xue, Y. Li, Sh. Guo, H. Zhao, W. Wang, X. Ma
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Abstract
This paper reports a study of plasma metabolites in hypertensive rats with syndrome of liver-fire hyperactivity in order to elucidate the biological basis of hypertension with syndrome of liver-fire hyperactivity. 1H-NMR method was used to identify and compare the small-molecule endogenous metabolites in the plasma of spontaneous hypertensive rats with liver-fire hyperactivity syndrome and normal rats. The results of 1H-NMR pattern recognition showed that hypertensive rats with liver-fire hyperactivity were significantly different from those of the control group. The results of 1H-NMR analysis indicated that there are close relationships between plasma metabolites and TCM syndromes, which is expected to be an objective diagnostic indicator in the further studies.

   
31

ERK/MAPK-mediated alleviation in cognitive dysfunction in chronically stressed mice treated with ethyl acetate extracts of Cynomorium Songaricum
Original Research Article
Pages 178 – 183
S.Y. Ma, H.S. Chang, D. Cheng, J. C. Zheng, F.Z. Tian, L.L. Li, X.J. Li, Y. Lu
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Abstract
This study explored the neuroprotective mechanism of ethyl acetate extracts of Cynomorium Songaricum Rup (ECS) in improving the cognitive dysfunction in chronically stressed mice. We tested the spatial learning and memory ability through water maze, the expression level of phosphorylated extracellular signal regulated kinase 1/2(P-Erk1/2) and phosphorylated cAMP response element protein (P-CREB) of mitogen-activated protein kinase (MAPK) signal pathway in the hippocampus. Besides, the expression of synaptophysin (Syn) and postsynaptic density protein 95 (PSD-95) was assessed. We also detected the long-term potentiation (LTP) by neurotic electrophysiology, observing the morphological change of hippocampal neurons by HE staining. The results showed that ECS could improve the learning and memory disorders caused by chronic stress in mice. This may be related to the raise in the expression of Syn and PSD-95 by activating the expression of P-Erk1/2 and P-CREB in MAPK signaling pathway.

   
32

Mechanical properties and microstructure of hot rolled NM360/Q345R composite interface analysis
Original Research Article
Pages 184 – 189
J. Li, L.Ma, G. Zhao, Q. Huang, X. Yang, M. Cheng
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Abstract
The rolling reduction rate is one of the important factors that affect the bonded interface of a composite plate. In this paper, the mechanical properties and microstructure of the interface were studied for 30%, 50% and 70% rolling reduction rates. The NM360/Q345R composite plates were analyzed by a universal tensile testing machine, OM, SEM and EDS. As the rolling reduction rate increased, both the tensile strength and the elongation increased. When the reduction rates were 30% and 50%, the bonding interface was poor and apparent cracks could be observed after the tensile tests. When the reduction rate reached 70%, no voids or cracks existed, the breaking interface was smooth and neat and the bonding interface formed a common structure. Significant decarbonization of NM360 occurred at the bonding interface. When the reduction rates were 30% and 50%, long strips or black dots of particles appeared near the interface. The black particles were Mn and Si oxides, which could have a negative effect on the bonding interface.

   
33

Benzothiazole-based ionic liquids (BIL)-induced acute toxicity attributed to damage to antioxidant enzyme system in zebrafish (Danio rerio)
Original Research Article
Pages 190 – 194
Y. Luo, H. Song, Y. Chen, G. Li, M. Zhu
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Abstract
Ionic liquids (ILs), considered to be green solvents, are widely distributed in the environment and thus exposure to these chemicals has attracted attention due to the potential adverse consequences on organisms and ecosystems. The aim of this study was to investigate the influence of benzothiazole-based IL (BIL) on zebrafish survival and determine whether oxidation was responsible for mortality. Zebrafish (Danio rerio) were exposed to 5 different concentrations of 4 acidic and one neutral IL solutions for 24 h and the 50% lethal concentrations (LC50) for each benzothiazole-based IL were determined and compared. Hepatopancreas samples were taken at the 6th, 12th, 18th and 24th h after exposure. Catalase (CAT) and glutathione peroxidase (GSH-Px) activity, as well as levels of reactive oxygen species (ROS) and malondialdehyde (MDA) were measured. Data demonstrated that BIL could significantly decrease hepatopancreas CAT and GSH-Px activity accompanied by an increase in the levels of reactive oxygen species ROS and MDA. It was also found that the toxicity of acidic ionic liquids was higher than that of neutral ionic liquids.

   
34

Large eddy simulation of multiphase flow in button - type micro channels
Original Research Article
Pages 195 – 199
Zh. He, J. Liu, X.-Y. Sun, X. Gu
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Abstract
The reduction of the micro channel scale creates surface tension, wettability cannot be ignored, the capillary action and the friction between the fluid and the wall also play an important role, which makes difficult the direct observation. In this paper, various structure-micro channels with cross-sectional area of 200 μm × 200 μm were taken as the research object. Numerical simulation based on Smagorinsky model and VOF model (for dealing with multiphase flow interface problems) was used as research method to study the mixing effect of fluids in the micro channel. The results showed that the distance between the two button nodes, the node diameter, the distribution position, and the channel entrance angle have a certain effect on the mixing effect in the micro channel.

   
35

Ecological response to land use change: a case study from the Chaohu lake basin, China
Original Research Article
Pages 200 – 206
B. Wang, L. Chen, L. Li, H. Xie, Y. Zhang
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Abstract
Land use change (LUC) has been considered as a major cause of global environmental change. Characterizing LUC and its impact on the eco-environment can contribute to the sustainability of regional development. In order to accurately assess the ecological response to LUC, this study proposed a land use change and ecological response (LUCER) framework by means of remote sensing, incorporating the land use transition matrix, remote sensing ecological index (RSEI), and spatial regression methods. The LUCER framework was tested on the Chaohu lake basin. Results showed that the LUC intensity of the study area increased significantly, but RSEI decreased by a large margin, and the change trend showed a U shape. Moreover, LUC was the Granger cause of RSEI and their correlation remained negative. The LUCER framework performed well in measuring the LUC and RSEI changes. Our research suggests that the LUCER framework could effectively explain the dynamic process and functioning mechanisms of LUC and RSEI changes and quantitatively evaluate the LUC ecological response. From an ecological environment protection perspective, the results of this study can provide an insight into land use decision-making for policy makers.

   
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37 CONTENTS