Determining the neutron star surface magnetic field strength of two Z sources

From the extreme position of disk motion, we infer the neutron star (NS) surface magnetic field strength B_0 of Z-source GX 17+2 and Cyg X-2. The inferred B_0 of GX 17+2 and Cyg X-2 are ~(1-5)X10^8 G and ~(1--3)X10^8 G}, respectively, which are not inferior to that of millisecond X-ray pulsars or atoll sources. It is likely that the NS magnetic axis of Z sources is parallel to the axis of rotation, which could result in the lack of pulsations in these sources.Comment: 2 page

Impact of Mountain Pine Beetle-Attacked Lodgepole Pine Logs on Veneer Processing

Pilot plant tests and mill trials were conducted to quantify the impact of using mountain pine beetle(MPB)-attacked lodgepole pine (Pinus contorta Dougl.) wood on green veneer processing, and determine if it makes economic sense to sort and process MPB logs separately from normal logs of white SPF (spruce-lodgepole pine-alpine fir) mix for plywood manufacturing. The results demonstrated that log dry-out, improper log conditioning, and veneer peeling contribute to the breakage of veneer ribbon, and in turn, loss of veneer recovery at the green end when processing MPB wood. Compared with the green SPF veneer controls, green MPB veneer has lower moisture content (MC) with smaller variation. The MPB veneer can be clipped narrower with an equivalent of 1% increase in recovery due to less width shrinkage, and be sorted more accurately requiring only two green sorts: heart and light-sap. The MPB veneer can also be dried faster with a reduction in drying time by about 25% for the heart veneer and 35% for the light-sap veneer. However, due to higher volume of narrower random sheets and increased waste from manual handling and composing, the net recovery of the MPB logs is about 8% lower than that of the control SPF logs. Furthermore, the color of the stained MPB veneer is lightened after drying, but it still causes interference with visual grading. Since MPB wood has unique MC and processing characteristics, it is recommended that it be sorted in the log yard when its proportion reaches about 10% of the total logs procured

Accessing provincial energy efficiencies in China's transport sector

The transport sector is attracting increasingly attention in the context of climate change and sustainable development, for its rapidly growing demand for energy and heavy reliance on oil products. Especially in China, where the demands for transportation are tremendous and ever-increasing, it is worthy to explore the provincial variations in energy efficiency in the transport sector, in order to enhance energy efficiency and to promote energy savings in this sector. By using stochastic frontier analysis (SFA) approach, this paper calculates the provincial energy efficiency as well as energy saving potential in China's provincial transport sector over 2007–2016. Results suggest that China's national average energy input efficiency in the transport industry is 0.673 during the sample period, which implied that relatively large degree of non-efficiency exists in this sector. Besides, the increase of government support (GS), the improvement of road condition (RC) and public transport (PT) are influencing factors for the improvement of China's provincial energy efficiency in the transport industry. Additionally, energy saving potential in the transport sector is also estimated in this paper. It is shown that, although energy efficiency in the eastern China is the highest (much higher than the country-wide level), the estimated absolute amount of the energy saving potential in the eastern area is significantly larger than those in the central area and western area due to the fact that the eastern area contributes to the largest share of the total energy consumption in this sector.</p

Veneer Surface Roughness and Compressibility Pertaining to Plywood/LVL Manufacturing. Part I. Experimentation and Implication

Extensive experiments were conducted to examine the transverse compression behavior of trembling aspen (Populus tremuloides) veneer at ambient and controlled temperature and moisture content (MC) environments, and the relationship between contact area, veneer surface roughness, and applied load. Based on the results, a novel method was developed to characterize surface roughness/quality of wood veneer in terms of its compression behavior. This method may have significant implication on both theory and practice. In theory, the general wood transverse compression theory needs to be revised to include four stages instead of the commonly defined three. The first stage, which has long been overlooked but is critically important, could be named "progressive contact." During this stage, the contact area increases nonlinearly with the load applied. It is this stage that reveals the interfacial contact of veneer-to-veneer or veneer-to-plate and the minimum veneer compression required for achieving adequate contact. With the inclusion of the first stage, the yield displacement also needs to be redefined. In practice, the method provides a fast and objective way of evaluating veneer surface roughness/quality for plywood/LVL manufacturing. Furthermore, the minimum compression required and yield displacement of wood veneer derived from its compressive load-displacement curve were found to be independent of temperature and MC, which helps benchmark material recovery in terms of veneer surface roughness/quality when manufacturing into quality plywood/LVL products. The method could also be applied to other wood composite elements such as wood strands

Veneer Surface Roughness and Compressibility Pertaining to Plywood/LVL Manufacturing. Part II. Optimum Panel Densification

In Part I of this series, a novel method was proposed to assess surface roughness/quality and compressibility of wood veneer, and the wood compression theory was revised to include the first stage of "progressive contact." Based on this revised theory, the minimum compression required can be established for achieving adequate contact of veneer-to-veneer (or plate), and true veneer yield displacement can be determined. Owing to the variation of veneer compressibility and random veneer placement in the panel assembly, this study aimed to apply the revised theory to establish the optimum panel densification for performance plywood and laminated veneer lumber (LVL) manufacturing. Using 3.2-mm-thick rotary cut trembling aspen (Populus tremuloides) veneer as an example, the correlation between the contact area and panel compression ratio (CR) was first established in terms of veneer surface roughness. Then, the required aspen panel CR and density were identified for achieving a target 80% contact area of veneer-to-veneer (or plate). Meanwhile, through the compression tests of 30- x 30-mm aspen veneer specimens, within-sheet and between-sheet variations in density, thickness, and compressibility were revealed. Furthermore, based on the frequency distribution of the minimum compression required and yield displacement for aspen veneer, the optimum range of aspen panel densification was identified with a CR ranging from 11.3% to 18.0%. Finally, through the manufacturing of aspen panels, such densification range identified was validated for improved panel quality, material recovery, and dimensional stability while achieving superior panel bending and gluebond performance