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1

The Bending, Impact Fracture Behavior and Characteristics of Stainless Steel Clad Plates with Different Rolling Temperature

An Q., Fan K. Y., Ge Y. F., Liu B. X., He J., Wang S., Chen C. X., Ji P. G., Tolochko O.

Archives of Metallurgy and Materials

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2021

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Vol. 66, iss. 1

229--239

EN

The interface characteristics, bending and impact behavior, as well as fracture characteristics of stainless steel clad plates fabricated by vacuum hot rolling at different rolling temperatures of 1100°C, 1200°C and 1300°C are investigated in detail. The interface bonding strength is gradually increased with the increasing rolling temperature due to the sufficient diffusion behavior of alloy element. The bending toughness and impact toughness are gradually decreased, while the bending strength increase with the increase of the rolling temperature, which is attributed to mechanisms of matrix softening and interface strengthening at high rolling temperature. Due to the weak interface at 1100°C, the bending and impact crack propagation path was displaced by delamination cracks, which in turn lead to reduction in stress intensity of the main crack, playing an effective role in toughening the stainless steel clad plates. Moreover, the impact fracture morphologies of clad plates show a typical ductile-brittle transition phenomenon, which is attributed to the matrix softening behavior with the increasing rolling temperature.

2

The effect of polyacrylic acid on the surface properties of calcite and fluorite aiming at their selective flotation

Zhang C., Gao Z., Hu Y., Sun W., Tang H., Yin Z., He J., Guan Q., Zhu Y.

Physicochemical Problems of Mineral Processing

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2018

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Vol. 54, iss. 3

868--877

EN

In this study, the polyacrylic acid (PAA) was studied as a selective depressant for calcite in the selective flotation of fluorite and calcite, and the implications of this process for the separation of fluorite ore were studied using micro-flotation tests, and the results were analyzed with Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS) analyses. The flotation tests indicated that the preferential adsorption of PAA onto calcite rather than sodium oleate (NaOl) could selectively depress the flotation of calcite, allowing its separation from fluorite at pH 7. The zeta potential of calcite became more negative with the addition of PAA rather than with NaOl. However, the characteristic features of PAA adsorption were not observed for fluorite, suggesting that NaOl preferentially adsorbed on the surface of fluorite, or that PAA could be replaced by NaOl on the fluorite surface. FT-IR and XPS analysis were utilized to obtain a better understanding of the mechanism by which PAA was more strongly adsorbed on the calcite surface than NaOl. This was revealed to occur through chemical bonding between the carboxyl group of PAA and the hydroxyl groups of the Ca species on the calcite surface, modifying the structure of the adsorbed layer. A possible adsorption mechanism, along with a postulated adsorption mode for the surface interaction between PAA and calcite, is proposed.

3

Risk of the maritime supply chain system based on interpretative structural model

He J., Xiong W., Cao Y.

Polish Maritime Research

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2017

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S 3

28--33

EN

Marine transportation is the most important transport mode of in the international trade, but the maritime supply chain is facing with many risks. At present, most of the researches on the risk of the maritime supply chain focus on the risk identification and risk management, and barely carry on the quantitative analysis of the logical structure of each influencing factor. This paper uses the interpretative structure model to analysis the maritime supply chain risk system. On the basis of comprehensive literature analysis and expert opinion, this paper puts forward 16 factors of maritime supply chain risk system. Using the interpretative structure model to construct maritime supply chain risk system, and then optimize the model. The model analyzes the structure of the maritime supply chain risk system and its forming process, and provides a scientific basis for the controlling the maritime supply chain risk, and puts forward some corresponding suggestions for the prevention and control the maritime supply chain risk.

4

A conceptual model of excellent performance mode of port enterprise logistics management

He J., Xiong W., Cao Y.

Polish Maritime Research

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2017

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S 3

34--40

EN

Port as one of the key hubs of international logistics, which has become the main part and the base of global logistics management. The port enterprises, plays an important role in the global supply chain. However, due to the lack of understanding in port supply chain management, coordination between the port enterprises, the integration of business process is not perfect, the lack of information sharing between various organizations, ports enterprises usually failed to fully play its positive role. Based on this, the paper makes the port enterprises as the research object, and introduces the excellent performance mode into the port enterprises. In order to study the port enterprises how to carry out effective quality management, and formation the coordination and integration of upstream and downstream of enterprises, so as to realize the competitive advantage in port logistics.

5

Mineralogical and chemical characteristics of the lead-zinc tailing and contaminated soil from the mine tailing pond in Hunan Province (China)

Li C., Zeng L., Fu J., Chen J., He J., He Z.

Physicochemical Problems of Mineral Processing

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2017

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Vol. 53, iss. 2

1133--1147

EN

The mineralogical and chemical characteristics of heavy metals in tailings and soils is an imperative for potential ecological risk assessment of metals to environment and heavy metals pollution prevention and control. The lead-zinc tailing and contaminated soil in and near the tailing pond were sampeled from a mine tailing pond in Hunan province (China), in which the chemical composition, phase composition and thermal behavior of tailing and soil were investigated. Furthermore, the petrography of lead-zinc tailing and chemical fractionations of Pb and Zn in the contaminated soil were studied in details. The mineral phases of lead-zinc tailing were galena, pyrite, chalcopyrite, sphalerite, quartz and fluorite, as distinguished by the reflected light microscopy and further proofed by the scanning electron microscope-energy dispersive spectrometer under the back scattered electron mode. Chemical fractionations were carried out by the European Community Bureau of Reference (BCR) sequential extraction procedure for Pb and Zn in the soil and the mild acido-soluble (F1), reducible (F2), oxidizable (F3), and residual (F4) fractions were 5.90, 75.24, 4.90 and 13.96% for Pb, and 47.74, 34.06, 9.59 and 8.61% for Zn, respectively. Subsequently, the individual contamination factor (ICF) of Pb and Zn were calculated as 6.16 and 10.61, respectively. The DTPA-available content of Pb and Zn in the contaminated soil were 39.9 and 170.7 mg·kg-1, respectively. The study provided a base for selecting remediation strategies in the studied area.

6

A Note on Spiking Neural P Systems with Homogenous Neurons and Synapses

Yu Y., Wu T., Xu J., Wang Y., He J.

Fundamenta Informaticae

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2017

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Vol. 150, nr 2

231--240

EN

Spiking neural (SN, for short) P systems are a class of computation models inspired from the way in which neurons communicate by exchanging spikes. SN P systems with homogenous neurons and synapses are a new variant of SN P systems, where the spiking and forgetting rules are placed on synapses instead of in neurons and each synapse has the same set of spiking and forgetting rules. Recent studies illustrated that this variant of SN P systems is Turing universal as both number generating and accepting devices. In this note, we prove that SN P systems with homogenous neurons and synapses without the feature of delay are also Turing universal. This result gives a positive answer to an open problem formulated in [K. Jiang, et al. Neurocomputing 171(2016) 1548-1555] “whether SN P systems with homogenous neurons and synapses are Turing universal when the feature of delay is not used”.

7

Badania początkowego okresu hydratacji spoiw żużlowo-alkalicznych

He J., Cai J., He J.

Cement Wapno Beton

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2017

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R. 21/83, nr 6

507--516

PL

W pracy badano, za pomocą pomiarów ciepła hydratacji oraz czasu wiązania zaczynów, wpływ rodzaju, składu i ilości aktywatora na proces hydratacji alkalicznie aktywowanego mielonego granulowanego żużla wielkopiecowego. W przypadku aktywatora w postaci szkła wodnego dla modułów krzemianowych w zakresie 0,8 – 2,0 czas wiązania zaczynów wydłużał się nieznacznie wraz ze zwiększaniem się modułu krzemianowego. Dla modułów mniejszych od 0,8 i większych od 2,0 czas wiązania znacznie się wydłużał. Wraz ze wzrostem modułu krzemianowego szkła wodnego wydłużał się również okres indukcji na krzywych szybkości wydzielania ciepła. Zwiększenie zawartości aktywatora z 3% do 6% Na2Oeq przy stałym module powodowało skrócenie czasu wiązania. W przypadku aktywacji NaOH, zależność ta była odwrotna. Dla spoiw aktywowanych NaOH wydzielanie ciepła hydratacji było bardziej intensywne, ciepło całkowite większe a okres indukcji krótszy niż w przypadku spoiw aktywowanych szkłem wodnym. Zwiększenie zawartości Na2O w aktywatorze powodowało zwiększenie całkowitego ciepła hydratacji niezależnie od rodzaju użytego aktywatora.

EN

In present work, heat of hydration and setting times measurements were used to investigate the influence of type, composition and amount of activator on the hydration process of alkali activated ground granulated blast furnace slag. In case of water glass used as an activator, for modulus within the range 0.8 - 2.0 setting time of pastes was increasing gradually. For water glass modulus values below 0.8 and over 2.0 significant increase of setting time was noted. Also duration of induction period on heat evolution curve was increasing with increase of modulus. Increasing activator amount expressed as Na2Oeq content from 3% to 6% at constant water glass modulus resulted in setting time shortening. In case of NaOH activated pastes, the reverse relationship was noted. For NaOH activated pastes, heat of hydration evolution was more intense, total amount of heat was higher and induction period was shorter comparing to pastes activated with water glass. Increase of Na2Oeq content within the system resulted in total amount of heat evolved increase independently of activator type.

8

Spatio-temporal assessments of rockburst hazard combining b values and seismic tomography

Li J., Gong S.-Y., He J., Cai W., Zhu G.-A., Wang Ch.-B., Chen T.

Acta Geophysica

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2017

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Vol. 65, no. 1

77--88

EN

A better understanding of rockburst precursors and high stress distribution characteristics can allow for higher extraction efficiency with reduced safety concerns. Taking the rockburst that occurred on 30 January 2015 in the Sanhejian Coal Mine, Jiangsu Province, China, as an example, the mechanism of rockburst development in a roadway was analysed, and a combined method involving b values and seismic velocity tomography was used to assess the rockburst in both time and space, respectively. The results indicate that before the rockburst, b values dropped significantly from 0.829 to 0.373. Moreover, a good agreement between a significant decrease in b values and the increase of the number of strong tremors was found. Using seismic tomography, two rockburst risk areas were determined where the maximum velocity, maximum velocity anomaly and maximum velocity gradient anomaly were 6 km/s, 0.14 and 0.13, respectively. The high-velocity regions corresponded well with the rockburst zone and large seismic event distributions. The combination of b values and seismic tomography is proven to have been a promising tool for use in evaluating rockburst risk during underground coal mining.

9

Numerical test on polystyrene tunnel seismic-isolation material

He J., Chen W., Zhao W., Huang S., Yao Y.

Polish Journal of Chemical Technology

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2016

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Vol. 18, nr 3

122--127

EN

Stress-strain mechanical properties of polystyrene foam plastic material were tested under different loading conditions. An empirical constitutive model for describing metal materials was proposed for the polystyrene plastic foam. The static and dynamic tests results show that the ductility and watertightness of the polystyrene plastic foam are significantly improved. At the same time, in order to check its seismic-isolation property, the high-performance foam concrete as filling materials of Galongla tunnel in Tibet was simulated by FEM. The simulated results show that the polystyrene plastic foam can remarkably decrease the stress and the plastic zone in final lining, so it can effectively reduce the seismic damage of the tunnel. Considering the seismic-isolation property and low price of polystyrene plastic foam, it is a good reference for the anti-seismic design of tunnels in high intensity zones.

10

Dry beneficiation and cleaning of chinese high-ash coarse coal utilizing a dense-medium gas-solid fluidized bed separator

He J., Tan M., Zhu R., Luo Z.

Physicochemical Problems of Mineral Processing

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2016

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Vol. 52, iss. 2

662--675

EN

Dry dense-medium fluidized bed separation provides a new alternative approach for coal beneficiation and cleaning. An indicator of segregation degree Sash was proposed to evaluate the stratified performance of coal samples by bed density. Fluidization stability of the bed was greatly enhanced by mixing a certain amount (21.53%) of fine magnetite powder (< 0.15 mm) into the fluidized media, which indicated a uniform density distribution as well as slight fluctuations in bed. It was found that the favorable density-segregation performance of 3–13 mm coarse coal occurred with a static bed height of 80 mm and a superficial gas velocity of 11.84 cm/s. The optimal segregation degree values of 0.67, 0.74 and 0.76 were obtained for 3–6, 6–10 and 10–13 mm coal samples, respectively. Low-ash clean coal with yields of 50.79, 56.83 and 61.24% were effectively acquired by the dry separation for various coal size fractions, respectively. Probable error values of 0.07, 0.055 and 0.05 g/cm3 were achieved, indicating good separation performance.

11

Improving separation efficiency of 6-1 mm coal by introducing vibration energy to dense medium gas-solid fluidized bed

He J., Zhao Y., Luo Z., Zhao J., Duan C., He Y.

Physicochemical Problems of Mineral Processing

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2015

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Vol. 51, iss. 1

95--108

EN

Effects of the vibration energy on the fluidization quality and separation performance of dense medium gas-solid fluidized bed were investigated experimentally. The magnetite powder with a wide size range of 0.3-0.074 mm was utilized as the basic medium solids. 6-1 mm fine coal sample from Yongcheng (China) was used to perform the separation experiments. The results indicate that the vibration amplitude A and superficial gas velocity U are greatly significant to the fluidization stability and the density distribution uniformity. Comparing with the bed without vibration, the optimal SP and Sρ values of 0.034 kPa and 0.018 g/cm3 are acquired in vibration bed with the operating factors of A = 1 mm, U = 1.8Umf, f = 15 Hz and Hs = 150 mm. The coal ash content was reduced from 27.84% to 9.50% at a separating density of 1.68 g/cm3 with a probable error E value of 0.505. The separation efficiency of 6-1mm fine coal is effectively improved by introducing vibration energy to dense medium gas-solid fluidized bed. The technology provides a novel approach to achieve high-efficiency separation of 6-1 mm fine coal in the arid and water-shortage areas.

12

Investigation on the preparation and mechanical properties of porous Cu35Ni15Cr alloy for a molten carbonate fuel cell

Li C., Chen J., Li W., Ren Y., He J.

Materials Science Poland

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2015

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Vol. 33, No. 4

887--893

EN

The preparation process of porous Cu35Ni15Cr alloy was studied in this paper. The effect of ball milling time and sintering temperature on the porosity of Cu35Ni15Cr alloy was identified. It was found that 18 h ball milling and 950 degrees C sintering are the most promising parameters for the preparation of porous Cu35Ni15Cr alloy. The products have a similar to ~62 % porosity. The alloy consists of an alpha phase and beta phase. The influence of deformation temperature and loading rate on the mechanical properties of Cu35Ni15Cr alloys was investigated. The results show that with decreasing deformation temperature, the yield strength and elastic modulus of the porous alloy increase. With the increase of loading rate, the yield strength of these alloys shows an increasing trend, but the elastic modulus is on a steady level.

13

A Hybrid Distribution Algorithm Based on Membrane Computing for Solving the Multiobjective Multiple Traveling Salesman Problem

He J., Zhang K.

Fundamenta Informaticae

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2015

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Vol. 136, nr 3

199--208

EN

The multiobjective multiple traveling salesman problem (MmTSP), in which multiple salesmen and objectives are involved in a route, is known to be NP-hard. The MmTSP is more appropriate for real-life applications than the classical traveling salesman problem (TSP), however it has not received the same amount of attention. Due to the high complexity of the MmTSP, a promising algorithm for solving it must be based on a global search procedure. This paper proposes a hybrid global search algorithm, that belongs to the membrane computing framework. The search behavior of the algorithm is enhanced by a communication mechanism. The multichromosome representation is considered to reduce the excess runtime. The effectiveness of the proposed algorithm is tested on the MmTSP with disparately-scaled objective functions, salesmen and problem sizes. The experimental results are compared with the NSGA-II and several evolutionary strategies with decomposition, including simulated annealing algorithm, hill climbing method, pure evolutionary algorithm, and genetic algorithm.

14

Error Analysis and Antenna Array Placement Optimization of Localization System for Partial Discharge in Substation

He J., Li M., Chen G., Wang Z.

Przegląd Elektrotechniczny

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2014

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R. 90, nr 7

104--107

EN

The measurement and diagnosis of partial discharge (PD) is accepted as one of the most valuable means for assessing the quality of high voltage (HV) power apparatus and its running status. However, the current partial discharge monitoring mainly based on equipment, which needs multi-process test equipment, high cost, and large maintenance engineering. This paper introduced the use of four antennas array to receive ultra-high frequency (UHF) signal, and define 3-D coordinate system, then located PD source in the field of the substation. Furthermore, this paper discussed the principles of the location algorithm based on time difference, analyzed the origin of its location error, then the connection of location error and the placement of antenna array and the error of time difference has been discussed theoretically. Finally, this paper provided the optimal placement of the radio frequency antenna array.

PL

W artykule opisano czteroantenowy odbiornik sygnału UHF w zastosowaniu do analizy źródła wyładowania niezupełnego. Analizowano błąd określenia pozycji źródła w zależności od rozłożenia systemu anten.

15

Ecological risk and economic loss estimation of heavy metals pollution in the Beijiang River

He J., Zhang H., Zhang H., Guo X., Song M., Zhang J., Li X.

Ecological Chemistry and Engineering. S

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2014

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Vol. 21, nr 2

189--199

EN

The distribution and extent of heavy metal accumulation in the fluvial sediment of the Beijiang River are described. The potential toxicity of this pollution was quantified using a consensus based sediment quality guidelines (SQGs) method and the Hakanson potential ecological risk index. The concentrations of Hg, As, Cu, Zn, Pb, Ni and Cr were high enough to damage the sediment biota on a frequent basis. The potential ecological risk was much higher in the downstream, urbanized reaches of the river than in the upstream reaches which are still rural, but all sections of the river posed at least a moderate level of ecological risk. Estimates of the economic loss associated with these pollutions were appreciable, and were mainly due to Hg and Cu. The Beijiang River basin is heavily polluted, posing environmental risks for the downstream reaches of the Pearl River, and economic loss to the whole watershed.

PL

W artykule opisano dystrybucję i stopień akumulacji metali ciężkich w rzecznych osadach rzeki Beijiang. Potencjalną toksyczność tych zanieczyszczeń obliczono za pomocą metody wytycznych jakości osadów (SQGs) opartej na konsensusie i za pomocą potencjalnego wskaźnika ryzyka ekologicznego Håkansona. Stężenia Hg, As, Cu, Zn, Pb, Ni i Cr były na tyle wysokie, aby uszkodzić biocenozy osadu. Potencjalne ryzyko ekologiczne było znacznie większe w dalszych, zurbanizowanych odcinkach rzeki niż na wcześniejszych odcinkach, które nadal są wiejskie, ale wszystkie odcinki rzeki reprezentowały co najmniej umiarkowany poziom ryzyka ekologicznego. Szacunki strat ekonomicznych związanych z tymi zanieczyszczeniami były znaczne, a to głównie ze względu na obecność Hg i Cu. Dorzecze rzeki Beijiang jest mocno zanieczyszczone, stwarzając zagrożenie dla środowiska w dalszym biegu rzeki Perłowej i możliwość strat ekonomicznych dla całej zlewni.

16

An automaton Constraint for Local Search

He J., Flener P., Pearson J.

Fundamenta Informaticae

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2011

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Vol. 107, nr 2/3

223-248

EN

We explore the idea of using automata to implement new constraints for local search. This is already a successful approach in constraint-based global search. We show how to maintain the violations of a constraint and its variables via a deterministic finite automaton that describes a ground checker for that constraint. We extend the approach to counter automata, which are often much more convenient than finite automata, if not more independent of the constraint instance. We establish the practicality of our approach on several real-life combinatorial problems.