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1

A numerical approach in applying panel method for the added mass of a group of sections in fluids

Zhang D., Li P., Wang Q., Yang Y.

Archives of Mechanics

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2023

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Vol. 75, nr 1-2

151--168

EN

This paper firstly expands an efficient numerical methodology developed from the source panel method to the added mass calculation of long column systems in fluid. Structures submerged in fluid are considered as two-dimensional and are discretized into a number of source panels. The influence coefficient matrices and the potential function are then calculated and the fluid forces are calculated by the unsteady Bernoulli equation. Finally, we utilize this present method to calculate the mass coefficients of some typical problems, which effectively verifies its feasibility and accuracy. This method takes into account both applicability and computational efficiency. On the one hand, in contrast to the analytical method which is only applicable to specific cross-sections, this method is applicable to arbitrary boundaries with C0 continuity in mathematics. On the other hand, this method requires less mesh and computation than commercial software. This paper extends the application of the source panel method which is widely used in aerodynamics to provide a reference for added mass calculation problems in engineering.

2

Study on striking ship with loading impact on the performance of the double hull oil tanker collision

Wu W., Yang Y., Zhang J., Lu J.

Polish Maritime Research

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2018

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S 2

42--48

EN

Due to the great danger of the collision of oil tankers, lots of research on the collision of oil tankers has been carried out. But, at present, the research on the collision of oil tankers mainly focuses on the loading condition of the struck ship, ignores the impact on the loading condition of the striking ship. However, during the actual oil tanker collision, the striking ship is generally in the state of loading. Therefore, it is necessary to carry out the analysis of the impact of the loading condition of the striking ship on the collision damage of the oil tanker. In this paper, the effect of striking ship with loading on the impact performance of the side structure during the collision of the cargo double hull oil tanker has been investigated. The ship collision model was established by using the finite element software ANSYS/ LS-DYNA which is based on 7000 tons of double hull oil tankers. Based on the analysis of the collision force, impact of striking speed changes, impact of striking deep changes and structural energy absorption during the collision process, the influence of the striking ship with loading on the damage mechanism and the impact performance of the double shell oil ship side structure was expounded. The results show that the influence of the striking ship with loading can be great to the damage to side hull during the research of the collision performance of the oil tanker.

3

Analysis of the breakthrough phenomena during heavy metal elution from a column packed with municipal waste incineration ash

Zhang W., Yang Y., Suganuma H., Kato S., Suzuki S., Kojima T.

Environment Protection Engineering

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2018

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Vol. 44, nr 3

63--78

EN

At some point during acid leaching column tests of heavy metals from municipal waste incineration ash, sudden and rapid elution of harmful elements was observed which was called the breakthrough (BT) phenomena. The mechanism was elucidated from the results of measurement of elemental and particle size distribution in the column and batch leaching tests as follows. At the first stage of experimental runs, CaCO3 was dissolved in acidic solution and pH profile along the bed is formed. Some of the minor elements of Zn and Al dissolved by acid at the upper part of the column are precipitated at bottom of the column, leading to the reduction of flow rate of the leachate solution. After leachate pH becomes low by the termination of dissolution of Ca, these deposits are dissolved and thus, the flow rate increases. Most of the trace elements behave as such, which causes the increase of harmful element concentrations in the eluate. Some drastic concentration increase of harmful elements in leachate may occur even after the long period of pseudo stable dissolution behavior in the land-fill site.

4

Synthesis, Characterization and Compatibility Studies of Poly(DFAMO/NIMMO) with Propellant and PBX Ingredients

Li H., Yang Y., Pan J., Wang W., Pan R., Zhu W.

Central European Journal of Energetic Materials

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2018

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Vol. 15, no. 1

85--99

EN

Oxetane-based polymers substituted with difluoroamino groups can be used as energetic binders in propellants and polymer-bonded explosives (PBXs). As a novel candidate, poly(3-difluoroaminomethyl-3-methyloxetane/3-nitratomethyl-3-methyloxetane) (PDN) was synthesized and its structure was established. Thermogravimetry (TG) and differential scanning calorimetry (DSC) were employed to investigate its thermal decomposition behaviour. The compatibility between PDN and some common ingredients of propellants and PBXs was evaluated by the DSC method. PDN with good thermal stability was synthesized via a cationic solution polymerization process. Additionally, it has improved compatibility with cyclotetramethylenetetranitramine (HMX), carbon black (C.B.) and lead carbonate (PbCO3) compared with homopoly(3-difluoroaminomethyl-3-methyloxetane) (PDFAMO). PDN could be used as a promising difluoroamino energetic binder in the future.

5

Microstructure and Mechanical Properties of Duplex Structured Mg-Li-Zn-Y Alloys

Su J., Yang Y., Fu X., Ma Q., Ren F., Peng X.

Archives of Foundry Engineering

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2018

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Vol. 18, iss. 1

181--185

EN

As-cast Mg-6Li-0.3Zn-0.6Y and Mg-6Li-1.2Zn-1.2Y (wt%) alloys were prepared and extruded at 260 ºC with an extrusion ratio of 25. The microstructure and mechanical behavior of as-cast and extruded alloys are reported and discussed. The results show that Mg-6Li-1.2Zn- 1.2Y alloy is composed of α-Mg, β-Li, and W-Mg3Zn3Y2 phases while Mg-6Li-0.3Zn-0.6Y alloy contains α-Mg, β-Li, W-Mg3Zn3Y2 phase and X-Mg12ZnY. After hot extrusion, the microstructure of specimens is refined and the average grains size of extruded alloys is 15 μm. Dynamic recrystallization occurs during the extrusion, leading to grain refinement of test alloys. Both the strength and elongation of test alloys are improved by extrusion. The extruded Mg-6Li-0.3Zn-0.6Y alloy possesses an ultimate strength of 225 MPa with an elongation of 18% while the strength and elongation of Mg-6Li-1.2Zn-1.2Y alloy are 206 MPa and 28%, respectively. The X-phase in Mg-6Li-0.3Zn- 0.6Y is beneficial to the improvement of strength, but will lead to the decrease of ductility.

6

Explorative study of rotary tube piercing process for producing titanium alloy thick-walled tubes with bi-modal microstructure

Zhang Z., Liu D., Yang Y., Pang Y., Wang J., Wang H.

Archives of Civil and Mechanical Engineering

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2018

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Vol. 18, no. 4

1451--1463

EN

In order to solve the existing problems in the manufacturing of titanium alloy thick-walled tubes (TATWs), an innovative plastic forming method for the preparation of TATWs using rotary tube piercing (RTP) process was studied. In this paper, the advantages and basic principles of the RTP process were described. A new finite element model is established to study the effect of the thermal parameters on the RTP process of TATWs. Based on the control variable method, two key problems of rolling block and severe temperature rise in the RTP process were all solved, and the TATWs with bi-modal microstructure were produced by the self-developed piercing mill. In addition, the microstructure uniformity of the pierced tube was analyzed. Based on the experimental and numerical investigations, it's found that the RTP process is a viable process for manufacturing TATWs with bi-modal microstructure.

7

Three-dimensional biomechanical modeling and simulation of trephine cutting cornea for keratoplasty

Su P., Lu D., Deng S., Zhang L., Hao Y., Yang Y.

Acta of Bioengineering and Biomechanics

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2018

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Vol. 20, no. 2

23--33

EN

Trephination is one of the basic operations of keratoplasty, and the biomechanical mechanism of the operation can be revealed based on three-dimensional modeling and simulation of trephine cutting cornea. Methods: Based on the analysis of the physical and biomechanical characteristics of corneal trephination, a three-dimensional numerical model of corneal trephination is built, where the cornea can be simplified to two layers structure including stroma and epithelium, and the trephine cuts the cornea under the vertical motion load and the rotational motion load. A three-dimensional failure criterion of corneal material is proposed based on the yield strength theory. On this basis, trephination simulation is carried out, and the units of corneal material are removed from the model when they meet the defined failure criterion. Results: Under the given parameters including the velocity, the angle and the angular velocity, the trephine force curves, include the linear cutting force and the rotary cutting force are obtained, and show the change of the forces with displacement during the process of trephination simulation. The maps of the equivalent stress show the destruction and deformation of the cornea. Then, the experiment of robotic trephination is carried out under the same parameters and the effectiveness of the simulation is evaluated. Conclusions: Based on mechanics theory and finite element method, the process of trephine cutting cornea has been reproduced, and the interaction mechanism is revealed, which lays the foundation for the development of real-time simulation and virtual system of the corneal surgery.

8

Knitted silk mesh-like scaffold incorporated with sponge-like regenerated silk fibroin/collagen I and seeded with mesenchymal stem cells for repairing Achilles tendon in rabbits

Tang L., Yang Y., Li Y., Yang G., Luo T., Xue Y., Zhang W.

Acta of Bioengineering and Biomechanics

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2018

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Vol. 20, no. 3

77--87

EN

A scaffold knit with natural sericin-free silk fibroin fiber possesses desirable mechanical properties, biocompatibility, ease of fabrication, and slow degradability. However, regenerated silk fibroin degrades faster than natural silk. In this study, natural silk fibroin fiber mesh-like scaffolds were prepared by a weft-knitting method and the pores were filled with sponge-like regenerated silk fibroin-collagen I. The microporous sponge and mesh-like scaffolds were fused to achieve gradient degradation of the scaffolds, and rabbit bone marrow mesenchymal stem cells (BMSCs) were seeded onto the scaffolds to form scaffold–BMSCs composites. The composites were implanted into gap defects made in the rabbit Achilles tendon. Twenty weeks after implantation, histological observation showed that tendon-like tissue had formed, collagen I mRNA was expressed, abundant collagen was generated, and that there was no obvious degradation of silk. The maximum load of the neo-Achilles tendon was 62.14% that of the natural Achilles tendon. These outcomes were superior to those obtained in the group implanted with a scaffold without BMSCs. These findings suggest the feasibility of constructing tissue-engineered tendons using weft-knitted silk scaffolds incorporated with sponge-like regenerated silk fibroin/collagen I and seeded with BMSCs, and show potential of the scaffold–BMSCs composites to repair Achilles tendon defects.

9

Separation of split shear waves based on a hodogram analysis of HTI media

Yang Y., Lu J., Wang Y.

Acta Geophysica

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2018

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Vol. 66, no. 4

643--658

EN

Although the shear-wave birefringence phenomenon affects the imaging of converted shear waves, it also provides a considerable amount of information on subsurface fracture development. Therefore, it is significant to separate split shear waves before seismic interpretation and reservoir prediction. In this paper, we propose a new method of split shear waves separation based on the polarization directions derived from hodogram analysis. Through the hodogram analysis, we find that the split shear-wave particle motions are within the range of a specific and fixed rectangle, which have relations with the fracture azimuth in strata. In addition, we found that a couple of split shear waves can only be fitted to the unique trajectory rectangle through the theoretical derivation. Based on this, we establish the trajectory rectangle through the wave vector calculation and calculate the fracture azimuth according to the fact that the one edge of the trajectory rectangle is along or perpendicular to the fracture azimuth. Synthetic data analysis shows that the calculation accuracy of fracture azimuth under the constraint of trajectory rectangle is less affected by the time delay between split shear waves than using the method of eigenvector–eigenvalue decomposition (EED). Therefore, we can obtain better results for separation of split shear waves using our method than using EED. Eventually, we propose an approach of layer stripping to deal with the problem that shear wave split several times due to the situation that different strata have different fracture azimuths. Synthetic data test indicates that our method can achieve higher calculation efficiency and faster convergence speed than the conventional eigenvector–eigenvalue decomposition method, even though the data are of a low signal-to-noise ratio. Moreover, field data applications show the effectiveness and potential of our method.

10

Simultaneous quantitative determination of active components in Tetrastigma hemsleyanum by RP-HPLC coupled with diode array detection

Zhu Y., Yin Q., Du P., Huang S., Yang Y.

Acta Chromatographica

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2018

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Vol. 30, no. 3

186--190

EN

An effective, reliable, and sensitive reversed-phase high-performance liquid chromatography (RP-HPLC) with diode array detector (DAD) method was investigated for simultaneous determination of polydatin, isoquercitrin, resveratrol, and nicotiflorin in Tetrastigma hemsleyanum. The chromatographic separation of the four compounds was carried out on a Welchrom ODS column (4.6 mm × 250 mm, 5 μm) by gradient elution with phosphoric acid (H3PO4) aqueous solution (0.4%)–methanol as the mobile phase, at the temperature of 30 °C and a flow rate of 1.0 mL/min. The detection wavelength was set at 270 nm. Under optimum conditions, the baseline separation of these four compounds can be performed within 30 min. The developed method was validated in terms of detection limit, quantification limit, linearity, precision, and recovery tests. Eventually, the established HPLC–DAD method was successfully applied to the simultaneous determination of polydatin, isoquercitrin, resveratrol, and nicotiflorin in the extract of herb T. hemsleyanum.

11

Determination of the aglycon moieties of glycosidically bound compounds in Flos Chrysanthemi by GC × GC–TOFMS

Zhou Y., Huang G., Li X., Chen F., Liu H., Yang Y., Fan Z., Jiang J., Yang J.

Acta Chromatographica

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2018

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Vol. 30, no. 3

195--199

EN

A credible method for determination of the aglycon moieties of glycosidically bound aroma compounds in Flos Chrysanthemi by comprehensive two-dimensional gas chromatography–time-of-flight mass spectrometry (GC × GC–TOFMS) has been proposed. The aglycon moieties of glycosidically bound aroma compounds were isolated using methyl-tert-butyl ether (MTBE) extraction following enzymatic hydrolysis. The GC × GC–TOFMS analysis was performed to comprehensively identify different forms of the released aroma components in Flos Chrysanthemi. The result shows that the limit of detection of the released aglycon moieties ranged from 0.3 to 3.1 ng/mL, the recovery of the released 1-octanol was better than 98.3%, and the intra-day and inter-day precisions of this method were 0.2 to 8.9% and 1.3 to 9.1%, respectively. The proposed method was applied to the analysis of four types of Flos Chrysanthemi (Chuju, Boju, Hangju, and Gongju). A total of 60 aglycon moieties of interest were identified in the four types of Flos Chrysanthemi. These aglycones mainly consisted of aliphatic, aromatic, monoterpene, C13-norisoprenoids, and miscellaneous compounds.

12

Research on quantifying the hydrophilicity of leached coals by FTIR spectroscopy

Wang J., He Y., Yang Y., Xie W., Ling X.

Physicochemical Problems of Mineral Processing

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2017

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Vol. 53, iss. 1

227--239

EN

Surface properties play important roles in characterization of structural parameters and the hydrophilicity index. Accurate analysis of the macerals rather than the average properties of the macerals and minerals are crucial for these parameters and indexes. In order to improve the accuracy of analyzing coal surface property, HF/HCl acid leaching was applied to eliminate the interference of minerals. FTIR was used to characterize the differences in surface chemical composition between raw and processed coal. Moreover, each functional group was analyzed quantitatively. Based on these quantitative data, the structural parameters and hydrophilicity indexes were calculated. From the results of FTIR, the peaks of mineral cover up the types of the organic peaks, such as -COOH and aromatic CH stretching. In addition, they decrease the intensity of the peak such as C=C and aromatics CHx out-of-plane deformation in the spectra of raw coals. However, it provided the accurate types and contents of organic functional groups of the macerals after acid leaching. The structural parameter results indicate that the values cannot reflect the coal ranks through the surface properties of raw coals while they show a good relationship with the degree of coalification in the analysis of processed coals. Besides, the hydrophilicity indexes are verified by the natural floatability of coal macerals of the processed coals. It is also found that the processed lignite coal cannot be floated despite elimination of the hydrophilic minerals. The main reason of hard-to-float property of lignite coal lies in a strong hydrophilicity of macerals.

13

Features of distribution of uranium and thorium in red mud

Gu H., Wang N., Yang Y., Zhao C., Cui S.

Physicochemical Problems of Mineral Processing

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2017

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Vol. 53, iss. 1

110--120

EN

Natural radioactive elements such as uranium and thorium restrict the use of red mud as building materials or additives, and may cause environmental problems. The distribution features of U and Th in red mud was studied from micro and macro analysis, using EPMA, LA-ICP-MS, and methods of mineralogy and beneficiation. Based on the micro-area scanning analysis, main chemical compositions in red mud, such as Ca, Al, Si, Na, and K are dispersive while Fe and Ti mainly tend to concentrate in granular phases. Based on the in-situ analysis, the distribution of main elements and most trace elements in micro-zone of red mud was homogeneous. In micro-zone area, the variation tendency of thorium content was similar with Y in red mud samples. By means of the methods of mineralogy and beneficiation, red mud samples were separated into different fractions. U and Th tend to be enriched in the low density fraction of the red mud. Th presented a high concentration in the finest particle size fractions of the red mud. Neither U or Th was regularly distributed in various magnetic red mud fractions. Thorium fingerprint peaks were determined in perovskite by EDX under TEM, which is proposed to be one of the radioactivity sources in Bayer red mud.

14

A Revised TOPSIS Method Based on Interval Fuzzy Soft Set Models with Incomplete Weight Information

Yang Y., Peng X.

Fundamenta Informaticae

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2017

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Vol. 152, nr 3

297--321

EN

Soft set theory was originally proposed by Molodtsov in 1999 as a general mathematical tool for dealing with uncertainty. However, it has been pointed out that classical soft set model is not appropriate to deal with imprecise and fuzzy problems. In order to handle these types of problems, some fuzzy extensions of soft set theory are presented, yielding fuzzy soft set theory. As a further research, in this work, we first propose concepts of interval fuzzy sets and interval fuzzy soft sets, define some operations on them and study some of their relevant properties, especially, the dual laws are discussed with respect to difference operation in interval fuzzy soft set theory. We then introduce a revised Technique for Order Preference by Similarity to an Ideal Solution (TOPSIS) method and choice value method for interval fuzzy soft set which the weight information is completely unknown. Meanwhile, an analysis of computation complexity is employed, also the discriminative power of two methods are shown. Finally, two illustrative examples are employed to show that they can be successfully applied to problems that contain uncertainties.

15

Natural Fibres From the Bark of Mulberry Branches for Textile Application

Dong Z., Ding Z., Zhang S., Zhang Y., Fan H., Yang Y.

Fibres & Textiles in Eastern Europe

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2017

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Vol. 25, no. 3 (123)

20--25

EN

Fibers with low gum content were extracted from the bark of mulberry branches by a combination of bacteria and peroxide treatments. The bark of mulberry branches, with 30% cellulose, is a copious and inexpensive source of natural fibers. However, fibers extracted by microwave, enzyme or alkali had a high gum content (15.5% for hemicellulose and 8.6% for lignin), which rendered them difficult to be made into high- value textiles. In this research, strains with high polygalacturonase activities and subsequent hydrogen peroxide decreased the hemicellulose content to 2.5% and lignin content to 2.4%. Mulberry fibers in our study could be spun into yarns with a fineness of 18.2 tex. Compared to flax yarns, mulberry fiber yarns had a tenacity 20% higher, an elongation 18% higher and an unevenness 30% lower. Cotton/mulberry fiber fabrics had softer and smoother hand than cotton/flax fabrics. Overall, the fibers in our study show better potential for industrial textile applications than those in previous studies.

PL

Kora gałęzi morwy jest bogatym i niedrogim źródłem włókien naturalnych. W pracy przedstawiono proces otrzymywania włókien z kory morwy z wykorzystaniem szczepów bakteryjnych oraz nadtlenku wodoru, co zmniejszyło zawartość hemicelulozy do 2,5% i zawartości ligniny do 2,4%. W porównaniu do przędz lnianych, przędze z włókien morwy wykazywały o 20% wyższą wytrzymałość, o 18% wyższe wydłużenie i o 30% niższą nierównomierność. Tkaniny bawełniane z dodatkiem morwy miały bardziej miękki i gładszy chwyt, niż tkaniny bawełniane z dodatkiem lnu. Stwierdzono, że metoda pozyskiwania włókien z kory morwy przy zastosowaniu bakterii i nadtlenku wodoru może być stosowana do wyodrębniania włókien morwowych w celu produkcji wyrobów o wysokiej wartości i szerokim spektrum możliwości zastosowań przemysłowych.

16

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.

17

Wear Process Analysis of the Polytetrafluoroethylene/Kevlar Twill Fabric Based on the Components’ Distribution Characteristics

Gu D., Fan B., Li F., Yang Y., Chen S.

Autex Research Journal

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2017

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Vol. 17, no. 4

295--302

EN

Polytetrafluoroethylene (PTFE)/Kevlar fabric or fabric composites with excellent tribological properties have been considered as important materials used in bearings and bushing, for years. The components’ (PTFE, Kevlar, and the gap between PTFE and Kevlar) distribution of the PTFE/Kevlar fabric is uneven due to the textile structure controlling the wear process and behavior. The components’ area ratio on the worn surface varying with the wear depth was analyzed not only by the wear experiment, but also by the theoretical calculations with our previous wear geometry model. The wear process and behavior of the PTFE/Kevlar twill fabric were investigated under dry sliding conditions against AISI 1045 steel by using a ring-on-plate tribometer. The morphologies of the worn surface were observed by the confocal laser scanning microscopy (CLSM). The wear process of the PTFE/Kevlar twill fabric was divided into five layers according to the distribution characteristics of Kevlar. It showed that the friction coefficients and wear rates changed with the wear depth, the order of the antiwear performance of the previous three layers was Layer III>Layer II>Layer I due to the area ratio variation of PTFE and Kevlar with the wear depth.

18

Microstructure and Mechanical Behavior of Mg-0.5Si-xSn Alloys

Fu X., Yang Y., Ma Q. Y., Peng X., Xu T.

Archives of Foundry Engineering

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2017

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Vol. 17, iss. 4

179--184

EN

Mg-0.5Si-xSn (x=0.95, 2.9, 5.02wt.%) alloys were cast and extruded at 593K (320 ºC) with an extrusion ratio of 25. The microstructure and mechanical properties of as-cast and extruded test alloys were investigated by OM, SEM, XRD and tensile tests. The experimental results indicate that the microstructure of the Mg-0.5Si-xSn alloys consists of primary α-Mg dendrites and an interdendritic eutectic containing α-Mg, Mg2Si and Mg2Sn. There is no coarse primary Mg2Si phase in the test alloys due to low Si content. With the increase in the Sn content, the Mg2Si phase was refined. The shape of Mg2Si phase was changed from branch to short bar, and the size of them were reduced. The ultimate tensile strength and yield strength of Mg-0.52Si-2.9Sn alloy at the temperature of 473K (200 ºC) reach 133MPa and 112MPa respectively. Refined eutectic Mg2Si phase and dispersed Mg2Sn phase with good elevated temperature stability are beneficial to improve the elevated temperature performance of the alloys. However, with the excess addition of Sn, large block-like Mg2Sn appears around the grain boundary leading to lower mechanical properties.

19

The flow line evolution of hot open ACDR process for titanium alloy discs

Zheng Y., Liu D., Zhang Z., Yang Y., Ren L.

Archives of Civil and Mechanical Engineering

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2017

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Vol. 17, no. 4

827--838

EN

Compared with traditional forging of titanium discs, the particular advantage for ACDR (axial closed die rolling) process is saving forming loading, but the weighted coefficient of compression and torsion happened on ACDR process show ambiguous even at the same axial forging ratio. Summed up from previous research, plastic yield process at ACDR forming is not only affected by the main stress caused from axial deformation, but also affected by shear stress from circumferential deformation. Flow line evolution as one of the manifestations, especially the circumferential deformation, should be studied to as basic theory to predict metal flow order, furthermore to define the deformation extent during ACDR process. Thus, this article presents flow line evolution laws with the three directions under different process conditions, emphasizing the difference of flow line evolution at different processing and the influence of process parameters associated with circles number n with the each direction. To achieve this purpose, numerical simulation with the essential boundary condition has been built. By means of systematic studying and discussing among deformation modes (stamping/machining, forging, high-pressure torsion, ACDR forming) and the process parameters (n, η, v, ω), the evolution law of flow line during hot ACDR on titanium alloy discs is achieved.

20

Orchards on Eroded Uplands of Southeast China: Sustainability or Abandonment?

Wang C., Yang Y., Pang W., Hong J.

Problemy Ekorozwoju

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2016

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Vol. 11, nr 2

37--43

EN

Orchard development on eroded uplands is considered as a successful method in integrating soil erosion treatment with economic development in many developing countries. However, much attention focused on its present achievements without thinking over the economic viability over long plantation duration. Orchards that have not been intensified seem to be threatened by complete abandonment. To illustrate the economic viability and sustain-ability of orchard management, we have deliberately focused on a case study in Southeast China. The results of economic viability based on a cost-benefit analysis showed that orchard management was barely economically sustainable. Their viability is assured if reduced labor costs and increased fruit price are accepted. Based on these results, recommendations are made to prevent the abandonment of orchards on degraded uplands and to preserve its environmental benefits.

PL

Tworzenie sadów na zerodowanych wyżynach w wielu krajach rozwijających się jest traktowane jako metoda udanie łączącą zintegrowane przeciwdziałanie erozji gleb z rozwojem ekonomicznym. Niestety, zbyt mocno podkreśla się znacznie szybkich osiągnięć, bez rozważania kontekstu wieloletniej opłacalności takich działań. Sady, których nie poddano modyfikacjom, opuszczono. By zilustrować ekonomiczną sensowność i zrównoważoność zarządzania sadami, wybrano jako case study obszar płd.-wsch. Chin. Rezultaty oceny opartej na analizie kosztów i korzyści wykazały, że zarządzanie sadami okazuje się być słabo ekonomicznie zrównoważone. Opłacalność zostałaby zapewniona w przypadku obniżenia kosztów pracy i podniesienia cen owoców. Na podstawie przeprowadzonych badań przedstawiono rekomendacje, których uwzględnienie umożliwiłoby zaprzestanie procederu rezygnacji z prowadzenia sadów na terenach zdegradowanych wyżyn i utrzymanie korzyści środowiskowych.