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1

Effect of modified starch on separation of fluorite from barite using sodium oleate

Chen Z., Ren Z., Gao H., Qian Y., Zheng R.

Physicochemical Problems of Mineral Processing

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2018

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Vol. 54, iss. 2

228--237

EN

In this study, a modified starch was utilized to selectively separate barite from fluorite. The results of flotation tests showed that highly selective separation of fluorite from barite was obtained when 250 mg/dm3 of modified starch and 13.16×10−5 mol/dm3 sodium oleate was used in neutral solutions. FTIR spectra results showed that the modified starch can adsorb on the fluorite and barite surfaces. Zeta potential analyses indicated that the modified starch had little effect on adsorption of sodium oleate on the fluorite surface, although it interfered with the adsorption of sodium oleate on the barite surface. Contact angle measurements results corresponded well with the flotation results.

2

Identifying the degree of luminescence signal bleaching in fluvial sediments from the Inner Mongolian reaches of the Yellow River

Li F., Pan B., Lai Z., Gao H., Ou X.

Geochronometria

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2018

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Vol. 45, no. 1

82--96

EN

The partial bleaching of the luminescence signal prior to deposition results in age overestimation, and can be a problem in delineating fluvial evolution within an OSL chronological framework. The Inner Mongolian reaches of the Yellow River are characterised by a high sediment load and complex sources of sediments. To test the incomplete bleaching occurring in this type of environment, the residual doses and the luminescence signal characteristics of different particle size fractions from 14 modern fluvial sediment samples were investigated. Furthermore, 26 OSL ages derived from drilling cores were compared with 11 radiocarbon ages. Our results show that the residual equivalent doses principally range between 0.16 and 0.49 Gy for silt grains, and between 0.35 and 3.72 Gy for sand grains of modern samples. This suggests that medium-grained quartz has been well bleached prior to deposition, and is preferable to coarse-grained quartz when dating fluvial sediments in this region. The results also show that the De values of coarse-grained fractions display a stronger correlation with distance downstream. In addition, a comparison of OSL and radiocarbon ages from drilling cores establishes further confidence that any initial bleaching of these sediments was sufficient. As a result, we believe that the studied fluvial samples were well bleached prior to deposition.

3

Some Novel Pythagorean Fuzzy Interaction Aggregation Operators in Multiple Attribute Decision Making

Gao H., Lu M., Wei G., Wei Y.

Fundamenta Informaticae

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2018

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Vol. 159, nr 4

385--428

EN

In this paper, we investigate the multiple attribute decision making problems with Pythagorean fuzzy information. Then, we utilize arithmetic and geometric operations to develop some Pythagorean fuzzy interaction aggregation operators: Pythagorean fuzzy interaction weighted average (PFIWA) operator, Pythagorean fuzzy interaction weighted geometric (PFIWG) operator, Pythagorean fuzzy interaction ordered weighted average (PFIOWA) operator, Pythagorean fuzzy interaction ordered weighted geometric (PFIOWG) operator, Pythagorean fuzzy interaction hybrid average (PFIHA) operator, Pythagorean fuzzy interaction hybrid geometric (PFIHG) operator, Pythagorean fuzzy interaction correlate aggregation operators, Pythagorean fuzzy interaction induced aggregation operators, Pythagorean fuzzy interaction induced correlate aggregation operators, Pythagorean fuzzy interactive power arithmetic and geometric aggregation operators. The prominent characteristic of these proposed operators are studied. Then, we have utilized these operators to develop some approaches to solve the Pythagorean fuzzy multiple attribute decision making problems. Finally, a practical example for selecting the service outsourcing provider of communications industry is given to verify the developed approach and to demonstrate its practicality and effectiveness.

4

Effects of hole perpendicularity error on load distribution in single-lap double-bolt composite joints

Li R., Xiao R., Ge E., Gao H., Bao Y., Liu X.

Engineering Transactions

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2018

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Vol. 66, iss. 1

3--19

EN

Although automated machines are widely used in composite structure manufacturing, manually drilled holes are usually necessary due to spatial constrains and holes with perpendicularity errors are occasionally generated as a result. Considering the anisotropic properties of composite material, the influences of hole perpendicularity error on mechanical performances of composite joints are different from those of isotropic material. In this study, the effects of hole perpendicularity error on load distribution in single-lap double-bolt composite joints are discussed. A finite element model is first developed and verified both by analytical and experimental results. Parametric studies are then carried out taking into consideration bolt torque and hole perpendicularity error, represented by hole tilting direction and tilting angle. It is found that the hole tilting direction significantly affects on load distribution in composite joints. Although the loads taken by bolts are not significantly affected, it may make one composite plate take more than 60% of total loads. In addition, the influences of tilting angle on load distribution can be ignored in most cases, and as for the bolt torque, it is to enhance the influence of hole tilting direction.

5

Effect of Cone Size on the Bonding Strength of Bimetallic Composite Pipes Produced by Drawing Approach

Zheng M., Zhao T., Gao H., Teng H., Hu J.

Archives of Metallurgy and Materials

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2018

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Vol. 63, iss. 1

451--456

EN

The effect of cone size on interfacial bonding strength of bimetallic composite pipe manufactured by drawing approach is studied on base of the plane strain assumption and ideal elastic-plastic model, a simple expression for the effect of cone size on the bonding strength of bimetallic composite pipes is proposed. The agreement of the predicted results with the experimental results shows the reliability.

6

Preparation of activated bentonite and its adsorption behavior on oil-soluble green pigment

Zheng R., Gao H., Ren Z., Cen D., Chen Z.

Physicochemical Problems of Mineral Processing

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2017

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Vol. 53, iss. 2

829--845

EN

The present research work focuses on effective preparation of activated bentonite (AB) and its application in removal of oil-soluble green pigment (OSGP) from either vegetable oils or food-processing wastewater. Mono-factor experiments were carried out to explore the effects of operation factors in preparation of AB. The parameters investigated were the effect of contact time, adsorbent dosage, initial OSGP concentration and temperature. The chemical composition, crystalline phases, microstructure and functional groups of prepared AB were characterized and evaluated by X-ray fluorescence (XRF), X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR), respectively. The adsorption kinetics and equilibrium isotherms were studied, finding that the adsorption process fitted better with the pseudo-second-order model and the Freundlich isotherm equation. In addition, thermodynamic parameters, such as standard the Gibbs free energy (ΔG°), standard enthalpy (ΔH°) and standard entropy (ΔS°) were also calculated, indicating that adsorption was spontaneous and endothermic. The findings of this investigation suggest that AB prepared through microwave activation as a cheap adsorbent holds great potential to remove oil-soluble green pigment in the wastewater treatment process.

7

Evaluation of sodium petroleum sulfonates with different molecular weights for flotation of kyanite ore

Chen B. Z., Gao H., Li Y., Jin J., Ren Z., Wang W.

Physicochemical Problems of Mineral Processing

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2017

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Vol. 53, iss. 2

956--968

EN

The flotation performance of sodium petroleum sulfonates with different molecular weights was evaluated for flotation of a kyanite ore, by investigating valuable mineral recovery-grade, flotation kinetics and gangue entrainment. The results indicated that the higher molecular weight of agent, the higher final cumulative kyanite recovery was, with the maximum value of 72% being obtained with KY-3 with the molecular weight of 438. The final cumulative kyanite grade initially increased, and then decreased with the molecular weight increasing. In other words, the maximum final cumulative kyanite grade (i.e. 89.05%) was obtained with KY-2 with the molecular weight of 392. The kyanite flotation kinetics followed the first order kinetics well, while the modified flotation rate constant showed a decreasing trend after the initial increase as the molecular weight increased. In addition, the overall entrainment degree decreased with decreasing molecular weight of sodium petroleum sulfonates. The use of KY-2 in kyanite flotation was an attractive option in comparison with KY-1 and KY-3.

8

Characterization of Dinophysis acuminata from the Yellow Sea, China, and its response to different temperatures and Mesodinium prey

Gao H., An X., Liu L., Zhang K., Zheng D., Tong M.

Oceanological and Hydrobiological Studies

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2017

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Vol. 46, No. 4

439--450

EN

Dinophysis species are distributed worldwide and cause diarrheic shellfish poisoning (DSP). This paper documents the first successful culture of a Dinophysis (DAYS01) strain taken off Xiaoping Island, the Yellow Sea, China. The strain was identified as Dinophysis acuminata Claparède & Lachmann by morphological and phylogenetic analysis. The effects of temperature and different Mesodinium prey on the physiological and toxigenic characteristics of D. acuminata DAYS01 were also investigated. The results showed that the toxin concentration (toxin amount per ml of culture) increased with an increase in cell densities. Okadaic acid (OA), dinophysistoxin 1 (DTX1) and pectenotoxin 2 (PTX2) were the major toxin components of DAYS01, with the highest recorded toxin content of 5.66, 0.56 and 192.87 ng ml-1 culture medium, respectively. The prey type significantly influenced the growth yield in Dinophysis cultures. There was an effect of prey on the total toxin content, suggesting that the origin or strain of ciliate directly impacted the D. acuminata blooms and the overall toxin concentration in the system.

9

Effects of hole-perpendicularity error on joint stiffness of single-lap double-bolt composite joints

Liu X., Yang Y., Gao H., Bao Y., Li R., Chen L.

Engineering Transactions

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2017

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Vol. 65, iss. 2

289--305

EN

To investigate the influence of hole-perpendicularity error on stiffness of single-lap doublebolt composite joints, a finite element model was first created and validated by using the analogical mass-spring based model proposed by McCarthy et al. The model was then modified by introducing hole-perpendicularity error, with which the influences of hole-perpendicularity error, which is represented by hole-titling angle, hole-tilting direction, and bolt torque on the joint stiffness are studied. It is found that the hole-tilting direction causes the joint stiffness to either increase or decrease, which depends on the relation between the hole-tilting direction and the loading orientation. In addition, the hole-tilting angle strengthens the influence of hole-tilting direction and the bolt torque plays the most important role among the three factors in affecting the joint stiffness.

10

A Simplified Approach for the Hydro-forming Process of Bi-metallic Composite Pipe

Zheng M., Gao H., Teng H., Hu J., Tian Z., Zhao Y.

Archives of Metallurgy and Materials

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2017

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Vol. 62, iss. 2A

879--883

EN

In this article, it aims to propose effective approaches for hydro-forming process of bi-metallic composite pipe by assuming plane strain and elastic-perfectly plastic material model. It derives expressions for predicting hydro-forming pressure and residual stress of the forming process of bi-metallic composite pipe. Test data from available experiments is employed to check the model and formulas. It shows the reliability of the proposed model and formulas impersonally.

11

Characteristics of cationic red x-grl adsorption by raw diatomite and diatomite concentrate

Ren Z., Guan J., Gao H., Tian J., Wen Y., Zheng R.

Physicochemical Problems of Mineral Processing

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2016

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Vol. 52, iss. 1

44--55

EN

Raw diatomite (RD) and diatomite concentrate (DC) were used for the adsorption of cationic Red X-GRL from aqueous solutions. Mono-factor experiments were carried out to investigate the effects of the operation factor, and adsorption kinetics, isotherms, thermodynamics and mechanisms were explored. Similar trend for X-GRL adsorption onto RD and DC was observed. The adsorption capacity of dyes increased slightly with temperature, and the neutral pH was the optimum level. The adsorption processes occurred in accordance with the pseudo second-order model and were well fitted by the Langmuir isotherm model. The main driving forces of the physical adsorption on the diatomite were electrostatic attraction and van der Waals force. The RD could uptake more X-GRL than DC due to its higher content of fine particle and therefore, due to higher surface area available for adsorption. Raw diatomite as a cheap absorbent for X-GRL removal can be suggested as a promising supplement to activated carbon.

12

Establishment of motion model for wave capture buoy and research on hydrodynamic performance of floating-type wave energy converter

Gao H., Li B.

Polish Maritime Research

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2015

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S 1

106--111

EN

Floating-type wave energy converter has the advantages of high wave energy conversion efficiency, strong shock resistance ability in rough sea and stable output power. So it is regarded as a promising energy utilization facility. The research on hydrodynamic performance of wave capture buoys is the precondition and key to the wave energy device design and optimization. A simplified motion model of the buoys in the waves is established. Based on linear wave theory, the equations of motion of buoys are derived according to Newton’s second law. The factors of wave and buoys structural parameters on wave energy absorption efficiency are discussed in the China’s Bohai Sea with short wave period and small wave height. The results show that the main factor which affects the dynamic responses of wave capture buoys is the proximity of the natural frequency of buoys to the wave period. And the incoming wave power takes a backseat role to it at constant wave height. The buoys structural parameters such as length, radius and immersed depth, influence the wave energy absorption efficiency, which play significant factors in device design. The effectiveness of this model is validated by the sea tests with small-sized wave energy devices. The establishment methods of motion model and analysis results are expected to be helpful for designing and manufacturing of floating-type wave energy converter.

13

A Data Dissemination Algorithm using Multi-Replication in Wireless Sensor Networks

Gao C., Hu X., Guo L., Xiong W., Gao H.

Przegląd Elektrotechniczny

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2013

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R. 89, nr 1b

91--93

EN

Many data dissemination techniques have been proposed to facilitate data storage and query processing. In this paper, we propose a Multi-Replication Storage (MRS) algorithm in Wireless Sensor Networks (WSNs). In MRS scheme, sensing data is collected and stored at the home nodes, which form an s-hop dominating set of the whole network. Meanwhile, each home node has some replication nodes, when the home node receives a data, it will send data copies to the replica nodes in order to facilitate data query. So the MRS algorithm can provide timely responses to queries. Moreover, proposed data dissemination scheme also discusses load balance. Analysis and simulations are conducted to evaluate the performance of our MRS algorithm. The results show that the MRS algorithm outperforms the external storage (ES) based scheme, local storage (LS) based scheme and the data-centric storage (DCS) based scheme.

PL

W celu gromadzenia i przeszukiwania danych stosuje się wiele technik rozpraszania danych. W prezentowanym opracowaniu proponujemy zastosowanie w bezprzewodowych sieciach czujnikowych algorytmu MRS (gromadzenie przy pomocy wielokrotnej replikacji).W schemacie MRS dane gromadzone i magazynowane są w węzłach wewnętrznych, które tworzą s-przeskokowy układ obowiązujący w całej sieci. Każdy węzeł wewnętrzny ma kilka węzłów replikacji i, w celu ułatwienia przeszukiwania, kopiuje do nich gromadzone przez siebie dane. Tak więc proponowany schemat rozpraszania może zapewnić przeszukiwanie w odpowiednim czasie. W opracowaniu zbadano również zrównoważenie obciążenia. Przeprowadzono analizę i symulację zaproponowanego algorytmu MRS. Wyniki pokazują, że algorytm MRS przewyższa schematy oparte o gromadzenie zewnętrzne (ES), gromadzenie lokalne (LS) i gromadzenie w centrach danych (DCS).

14

Decentralized Fuzzy PID Excitation controller Combined with Turbine Regulating for Voltage Stability in Power Systems

Gao H, Hu X., Wang B., Qi H.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 10a

284-288

EN

This study deals with the design of a decentralized fuzzy proportional–integral–derivative (PID) excitation controller combined with turbine regulating to enhance the voltage stability in power systems after start-up or sudden disturbances. Based on the turbine regulating, we design the fuzzy PID (FPID) excitation controller combined with turbine regulating (FPID-TR). Simulation results show the effectiveness of the proposed controller for stabilizing the voltage in power systems.

PL

W artykule opisano sterownik PID wzbudzenia połączony z regulacją turbiny zastosowany w celu poprawy stabilności systemu energetycznego przy nagłych zakłóceniach. Sterownik wykorzystuje logikę rozmytą. (Sterownik PID wzbudzenia połączony z regulacją turbiny w celu poprawy stabilności systemu energetycznego)

15

Application study on cooperative drainage technology for mining-affected pressure relief gas in overlaying adjacent seams

Wang K., Zang J., Zhou A., Gao H.

AGH Journal of Mining and Geoengineering

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2012

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Vol. 36, no. 3

385-393

EN

During the mining process of 12# coal seam in Yangquan mine area, gas quantity emitting from overlaying adjacent seams was high and gas concentration in upper corners and return airways of mining faces often exceeded limitation. To solve these problems, through the combination of theoretical study, numerical simulation and on-site observation, the high-low zoning enrichment law of the mining-affected pressure relief gas in overlaying adjacent seams of 12# coal seam was formulated. According to this law, the cooperative drainage technology was proposed, namely arranging the high-located and low-located boreholes to drain the gas respective in high and low enrichment zones. By applying the cooperative drainage technology, the safety production status of mining faces of 12# coal seam in Nanzhuang mine has been significantly ameliorated, advance efficiency, drainage rate and drainage quantity have been improved greatly, carbon emission has been reduced and the environment has been protected, resource utilization has been improved, the service life of the mine will be extended. In a word, good economic, social and environmental benefits have been achieved, meanwhile, a safe, efficient, and sustainable exploitation of the mine has been realized.

PL

Podczas eksploatacji ściany nr 12 w Yangquan zanotowano dużą ilość gazu wydobywającego się z przyległych pokładów węgla. Koncentracja metanu w chodniku nadścianowym bardzo często przekraczała wartości dopuszczalne. Aby rozwiązać te problemy, sformułowano zasadę wysokiego/niskiego odmetanowania dla dekompresji metanu w przyległych do ściany nr 12 pokładach węgla na podstawie symulacji numerycznych oraz obserwacji. W odniesieniu do tej zasady zaproponowano technologię łączonego odprowadzania gazu poprzez otwory wiertnicze zlokalizowane odpowiednio na niższym i wyższym poziomie odpowiednich stref metanowości. Zastosowanie technologii odprowadzania łączonego przyczyniło się do znacznej poprawy bezpieczeństwa produkcji na przodku nr 12 kopalni Nanzhuang, zwiększenia wydajności, prędkości odprowadzania i ilości odprowadzanego gazu, obniżenia emisji dwutlenku węgla oraz lepszej ochrony środowiska, a także lepszego wykorzystania zasobów i wydłużenia okresu eksploatacji kopalni. Krótko mówiąc, uzyskano znaczne korzyści ekonomiczne, społeczne i środowiskowe, przy jednoczesnym zapewnieniu bezpiecznej, wydajnej i zrównoważonej eksploatacji kopalni.

16

Upper and lower solutions method for fourth-order periodic boundary value problems

Weng S., Gao H., Jiang D., Hou X.

Journal of Applied Analysis

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2008

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Vol. 14, nr 1

53-61

EN

The purpose of this paper is to prove the existence of a solution of the following periodic boundary value problem {u(4)(t) = ∫(t, u(t), u" (t), t ∈ [0, 2π] {u(0) = u(2π]), u' (0) = u' (2π), u" (0) = u' (2π), u''' (2π) in the presence of an upper solution β ≤ α, where ∫(t, u, v) satisfies one side Lipschitz condition.

17

Bio-inspired mechanics of bottom-up designed hierarchical materials: robust and releasable adhesian systems of gecko

Yao H., Gao H.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2007

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Vol. 55, nr 2

141-150

EN

To explore the basic principles of hierarchical materials designed from nanoscale and up, we have been studying the mechanics of robust and releasable adhesion nanostructures of gecko [1]. On the question of robust adhesion, we have introduced a fractal-like hierarchical hair model to show that structural hierarchy allows the work of adhesion to be exponentially enhanced as the level of structural hierarchy is increased. We show that the nanometer length scale plays an essential role in the bottom-up design and, baring fracture of hairs themselves, a hierarchical hair system can be designed from nanoscale and up to achieve flaw tolerant adhesion at any length scales. For releasable adhesion, we show that elastic anisotropy leads to orientation-dependent adhesion strength. Finite element calculations revealed that a strongly anisotropic attachment pad in contact wit h a rigid substrate exhibits essentially two levels of adhesion strength depending on the direction of pulling.

18

Synthesis, Crystal Structure and Properties of Transition Metal-Azide Compounds with Bis(pyrazol-1-yl)methane

Zhang L., Gao H., Ge Y., Peng F., Xue H.

Polish Journal of Chemistry

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2006

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Vol. 80, nr 9

1465-1471

EN

Two new compounds, Co(bpm)2(N3)2 (1) and {[Ni(bpm)2(H2O)2][Ni(bpm)2(N3)2]}(ClO4)2 (2), where bpm refers to bis(pyrazol-1-yl)methane, have been prepared and characterized by elemental analyses, IR, UV-Vis spectra and X-ray diffraction. Crystal data for 1: monoclinic, space group P21/n with a = 10.394(4), b =14.410(5), c = 12.591(4) Alfa,Beta = 91.194(7)°, V =1885.6(11) Alfa3 and Z= 4. Crystal data for 2: triclinic, space group P1with a = 8.7673(6), b = 8.9618(6), c = 13.5653(9) Alfa, alfa = 84.6040(10) , beta= 84.4230(10) , _ = 79.6040(10), V = 1040.19(12) Alfa3 and Z = 1. Complex 1 is a neutral monomer molecule, in which CoII ion is coordinated by four nitrogen atoms from two chelating bpm and two terminal azide ligands to form a cis-octahedral configuration. However, compound 2 is composed of a neutral [Ni(bpm)2(N3)2] entity, one [Ni(bpm)2(H2O)2]2+ cation and perchlorate anions, in which the neutral Ni(bpm)2(N3)2 entity is in a trans-six-coordinated configuration. The uncoordinated terminal nitrogen atom of azide forms O-H.....N hydrogen bonds with the coordinated H2O molecule to afford a one-dimensional chain structure.

19

Studies on the Electron Transfer reaction Mechanism Between NO2 and NO- 2 Complexes in the Gas Phase

Zhou Z., Gao H., Fu H., Du B.

Polish Journal of Chemistry

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2003

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Vol. 77 / nr 12

1849-1856

EN

The electron transfer (ET) reaction between NO2 and NO2 complexes in the gas phase is investigated by Density functional theory (DFT). The geometry optimization of the nitrogen dioxide complexes and the precursor state in the process of ET reaction was performed at 6-311+G* basis set level. The nitrogen dioxide molecule separation distances computed using DFT method were found to agree with second order Moller-Plesset perturbation theory level (MP2) results. The 351.1 nm (3.532 eV) photoelectron spectrum of the nitrite anion (NO2 ) is obtained. For the precursor complex of NO2….NO2 , eight reasonable geometries on the potential energy surface are considered with the most stable structure being T1-type. The activation barriers and the coupling matrix elements in the electron transfer process are also calculated for four different transition states. Results indicate that the structures and properties of the precursor complex directly affect the electron transfer reaction mechanism and rate. The reacting system in the T1-type structure has lower activation barriers and greater coupling matrix elements than those in other type of structures. It is indicate that the most possible path of the electron transfer is the collision of NO2 andNO2 to form the precursor complex with the T1-type structure, then the electron transfer and structure organization take place, the successor is obtained via the transition state with a Đ6 9-conjugated system. Finally the product is attained.