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China is not only the biggest importing country of the raw materials of forest products, but also the biggest exporting country of intermediate and final forest products. The paper aims to discuss these issues.

The authors use the Khandelwal (2010) method and trade data from 2000 to 2014 of bilateral forest products between China and ten main developed countries to evaluate the quality of China’s forestry imports and exports. Subsequently, the influencing factors of product quality are analyzed.

The results show that the current export quality of plywood and fiberboard is decreasing, and the export quality of particleboard and paper products is on the rise. A further study finds that several factors have the positive effects on the quality of forestry exports, including gross domestic product of the importing country, forestry export value of the importing country as well as the number of forestry higher education graduates of the exporting country. Moreover, the study also finds that the status of an Asia-Pacific Economic Cooperation member has a negative effect on the quality of forestry exports, while the distance cost has a negative influence on fiberboard, paper and paperboard.

The study suggests that China needs to strengthen the research and development investment on forest products, and improve the quality of forest products to promote the trade development of forestry exports.

The existing literature has not shown much research regarding the quality of China’s forestry exports through econometric analysis. Therefore, the research results provide new perspective about the influencing factors on China’s forestry trade activities.

This paper aims to evaluate the dynamic performance of hybrid roller bearings under lubricant contamination.

Some steel rollers in traditional cylindrical thrust roller bearings were replaced with ceramic rollers to assemble hybrid roller bearings. Friction experiments were conducted under lubricant contamination using alumina as the contaminant, and simultaneous vibration acceleration signals from the bearings were collected to evaluate their tribological and dynamic performance.

Under lubricant contamination, hybrid roller bearings with a sufficient number of ceramic rollers exhibit greater wear resistance compared to traditional all-steel bearings. There is a noticeable suppression of energy in both tangential and normal frequency bands of the bearings, with more pronounced suppression observed in higher frequency bands.

This study provides valuable insights for the development of hybrid ceramic bearings.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-08-2024-0291/

This study aims to develop a novel self-lubricating thrust roller bearing and analyze its tribological behavior under various groove characteristics in lubricant-free environments, based on the bearing’s motion characteristics.

The groove characteristics, including the groove surface area relative to the friction region, the angle between the groove’s lubrication direction and the roller’s axial rotation and groove depth, were investigated. Grooves were created on the bearing shaft washer using an optical fiber laser marking machine, and solid self-lubricating materials were applied via scraping. Tribological performance and surface morphology were analyzed using a friction-wear test rig and a three-dimensional noncontact profilometer. The lubrication mechanisms of the novel thrust roller bearing were then examined under varying groove characteristics.

Thrust roller bearings with lubrication grooves demonstrated superior tribological performance, significantly reducing wear. The optimal configuration, with a 10% groove area, 45° groove orientation and 320 µm depth, resulted in the lowest wear, friction coefficient (0.002), wear loss (4.8 mg) and temperature (30.67°C). Compared to bearings without grooves, coefficient of friction decreased by 92.59%, wear loss dropped by 93.15% and temperature reduced by 56.94%.

This study introduces a novel design for a self-lubricating thrust roller bearing, which enables self-lubrication in environments without traditional lubricants. A comprehensive examination of its surface characteristics, lubrication mechanisms and tribological behavior has been conducted. This research provides valuable insights for the study and application of thrust roller bearings.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-12-2024-0460/

This paper aims to analyze the frictional performance of the phosphated CTRBs under dry sliding conditions. Through friction and wear experiments and characterization analysis, this paper investigated the wear mechanism and anti-wear mechanism of the composite phosphating coatings.

This paper used a method of incorporating graphite particles and polytetrafluoroethylene (PTFE) particles into manganese-based phosphating solution to prepare composite phosphating coatings applied on cylindrical thrust roller bearings (CTRBs).

The results are as follows: the inclusion of functionalized graphite particles affects the characterization of the composite phosphating coatings, whereas PTFE particles serve a physical filling role and have no influence on the surface features of the composite phosphating coatings. The surface roughness of the composite phosphating coatings is the main factor affecting the frictional behavior of phosphated CRTBs. Roughness affects the amount of PTFE particles adsorbed on the surface of the phosphate crystals. PTFE particles can form a solid lubricating film at the friction interface, and under the same surface roughness conditions, phosphated CTRBs with added PTFE particles can improve its friction performance.

The characterization parameters of the composite phosphating coatings were controlled by adding functionalized graphite particles to the phosphating solution. The effects of adding only graphite particles and adding both graphite particles and PTFE particles on the surface characteristics of the phosphating coatings were discussed separately. The tribological performance of phosphating CTRBs was analyzed through friction and wear testing, and the influence of surface characteristics on wear mechanisms and anti-wear mechanisms was discussed.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-10-2024-0405/

The purpose of this paper is to develop a new type of embedded solid self-lubricating thrust ball bearing for conditions where grease lubrication cannot be used and to analyze its tribological performance under different lubrication characteristics (lubrication position, width and filling amount).

Lubrication parameters such as position (a), width (W) and filling amount (Q) were considered. Grooves were made on the raceway with a fiber laser and solid self-lubricating materials were applied through scraping. The frictional behavior of the new bearing was analyzed using a vertical test rig and the bearing’s surface topography was examined with a noncontact profilometer to study wear mechanisms.

The new inlay thrust ball bearings exhibited excellent lubrication effects and effectively controlled the temperature rise of the bearings. When a is 0 degrees, W is 0.5 mm and Q is 16 mg, the bearing experiences the least wear, and the friction coefficient and temperature are the lowest, measuring 0.001 and 41.52 degrees, respectively. Under the same experimental conditions, compared to smooth bearings without solid lubrication, the friction coefficient decreased by 96.88% and the temperature decreased by 59.74%.

This study presents a self-lubricating thrust ball bearing designed for conditions where grease lubrication is not feasible. A comprehensive investigation was conducted on its surface morphology, wear mechanisms and tribological performance. This work provides valuable insights into the research of self-lubricating thrust ball bearings.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-03-2024-0073/

The purpose of this paper is to reveal the friction and wear performance of grooves textured cylindrical roller thrust bearings with different groove dimensions under starved lubrication.

The groove dimensions include: width of grooves (WOG, 50 µm, 100 µm and 150 µm), depth of grooves (DPOG, 7 µm, 11 µm and 15 µm) as well as groove deflection angle (GDA, 45°). A fiber laser marking system was used to prepare groove patterns on the raceways of shaft washers. The friction and wear properties of grooves textured bearings were researched through a vertical universal wear test rig using a customized roller bearing tribo-pair under starved lubrication. Static finite element analyses were conducted to reveal their surface stresses. Through the comprehensive comparison and analyses, the influence mechanism of grooves on the tribological behavior of cylindrical roller thrust bearings was proposed and discussed.

When grooves textured bearings run under starved lubrication, their average coefficients of friction (COFs) and wear losses are all significantly reduced and much lower than those of smooth group. The influence of DPOG on the COF curves is significant, while the influence of WOG on the COF curves is a little weak. The influence of groove dimensions on the surface stresses of grooves textured bearings is weak, whether the WOG or DPOG. In this work, when the WOG is 100 µm and the DPOG is 15 µm, its average COF and wear loss are both the lowest, 0.0066 and 0.61 mg, respectively. Compared with the data of smooth group, its friction coefficient is reduced by 75.3% and its mass loss is reduced by 95.8%, showing a significant improvement in this condition.

This work can provide a valuable reference for the raceway design and reliability optimization of rolling element bearings.

The purpose of this paper is to study a new liquid-phase assisted texture treatment method to improve the tribological properties of 304 stainless steel.

Three groups of textured type (KY, KJ and YJ) were prepared on 304 stainless steel surface using laser circular and cross scanning method in air and liquid assisted condition. The surface morphology and element content of test samples were measured with scanning electron microscope, energy spectrum. Then, the tribological test was carried out using MWF-500 reciprocating friction and wear testing machine under dry and oil lubrication condition.

The experimental results showed that the textured surface of laser processing in air was obviously blackened, and the oxygen content was increased from 16.9% to 24%. These cases did not occur on liquid-assisted laser textured surface, which induced a better wettability and surface texture processing quality. For friction test, the friction coefficient of cross-scanning textured surface prepared in assisted liquid (YJ) was the smallest. It is reduced by 55% in oil lubrication case compared to the original surface (YS). The cross-scanning textured surface prepared in air (KJ) was a little worse in friction coefficient and a little better in wear quantity than the cross-scanning textured surface prepared in assisted liquid (YJ). It is indicated that the laser processing surface with assisted liquid has obvious advantages in surface texture quality and interfacial tribological property. The main reason is that the assisted liquid plays a role in cooling and protecting action of the machined surface. The bubbles, generated at the solid–liquid interface because of the laser heat effect, scatter the laser beam and carry out the processed melt meanwhile. The lubricating medium is easier to penetrate and store in the contact interfaces because of the higher surface textured performance and wettability.

The main contribution of this work is in providing a new surface texture processing method that has a better surface micropits quality and interfacial tribology regulation ability.

The purpose of this paper is to reveal the influence of dimples on the tribological properties of the “washers-cage-rollers” system of rolling element bearing (REB) under starved lubrication.

A fiber laser marking system was used to prepare dimples patterns on the raceways of the shaft washers of cylindrical roller thrust bearings (CRTBs). The friction and wear properties of dimples textured CRTBs with different diameter of dimples (200 µm, 250 µm, 300 µm) and depth of dimples (4 µm, 8 µm, 12 µm) were researched through a vertical universal wear test rig using a customized tribo-pair under starved lubrication. The surface stresses and the influence mechanism of dimple units on the tribological behavior of REBs were also compared and discussed.

Although the surface stresses on the raceways of dimples textured bearings are significantly higher than that of the smooth group, the coefficients of friction and wear losses of them are all reduced under starved lubrication. When the effective volume of dimples is between 1.13 and 2.25 and the depth of dimples is smaller than 12 µm, the tribological properties of dimples textured CRTBs are significantly improved. In this work, when the diameter of dimples is 250 µm, and the depth of dimples is 8 µm, the textured bearings can provide the excellent friction-reduction ability and outstanding wear resistance.

This work is a valuable reference for the raceway design and optimization of REBs.

In 2007, Dr. Biwang Jiang, a scientist, returned to China to establish NanoMicro. For the first decade, he exemplified the spirit of a scientist by focusing intensively on the field of nanospheres. His perseverance in research and his breakthroughs in leading international technologies allowed him to identify two major application areas: flat panel displays and biopharmaceuticals. The flat panel display business helped his startup survive the initial years, while the rise of the biopharmaceutical sector provided the growth needed for the company's eventual listing on the Shanghai Stock Exchange Sci-Tech Innovation Board (SSE STAR Market). What distinguishes entrepreneurship by scientists? Should technology-driven companies find markets for their technologies, or should they develop technologies to meet market demands?

Post-acquisition control is a crucial factor affecting acquisition performance. We investigate how post-acquisition control strategy affects cross-border acquisition performance of Chinese multinational enterprises (MNEs) through a configurational perspective.

Based on 70 cross-border acquisition cases by Chinese MNEs, we adopt fuzzy-set qualitative comparative analysis (fsQCA) to study the combined effects of strategic control, operational control, institutional distance, cultural distance, relative capacity and business relatedness on the cross-border acquisition performance.

On the basis of fuzzy set analysis of multiple interdependent factors, we identify six configurations that are conductive to achieving high cross-border acquisition performance and two configurations that relate to the absence of high performance, thus shedding light on the casually complex nature of performance drivers of acquisitions.

This study provides a holistic, configurational approach to investigating cross-border acquisition performance by emerging market firms. Our results provide some compelling evidence that accounts for the causal complexity of post-acquisition control strategies and acquisition outcomes in the context of emerging economies.