@article{chen_hu_chang_li_2007, title={Micro analytical methods for determination of compression wood content in loblolly pine}, volume={27}, ISSN={["1532-2319"]}, DOI={10.1080/02773810701700810}, abstractNote={Abstract All loblolly pine trees, especially the juvenile portion, contain various amounts of compression wood. The morphological, chemical, and papermaking properties of compression wood are distinctively different from those of normal juvenile wood and mature wood. Compression wood has higher lignin and galactan, but lower cellulose and mannan content, shorter average fiber length, lower fiber width but thicker cell wall, higher fiber coarseness and higher microfibril angles as compared with the corresponding normal wood. Micro analytical methods have been developed to quantitatively determine the percentage of compression wood in an incremental core so as to eliminate the effects of compression wood on the aforementioned properties. This enables accurate quantitative genetic analyses of these properties for tree breeding programs.}, number={3-4}, journal={JOURNAL OF WOOD CHEMISTRY AND TECHNOLOGY}, author={Chen, Qing-min and Hu, Zhoujian and Chang, Hou-min and Li, Bailian}, year={2007}, pages={169–178} }
 @article{khan_chen_yang_sun_lim_temkin_schetzina_shur_1997, title={UV, blue and green light emitting diodes based on GaN-InGaN multiple quantum wells over sapphire and (111) spinel substrates}, volume={43}, ISSN={["0921-5107"]}, DOI={10.1016/s0921-5107(96)01903-4}, abstractNote={Recently Nakamura et al. have reported on high brightness visible LEDs based on AlGaN-InGaN multiple quantum wells (MQWs) using atmospheric pressure metal-organic chemical vapor deposition (MOCVD) and AlGaN barrier layers around an InxGa1 − xN-InyGa1 − yN multiple quantum well region. We now report the fabrication of high brightness vertical cavity UV, blue and green light emitting diodes using low pressure MOCVD with GaN-InxGa1 − xN multiple quantum wells surrounded by GaN barrier layers. Our device structures over sapphire and cubic (111) spinel substrates consisted of a 10 period GaN-InGaN MQW (25 Å well-50 Å barrier) surrounded by n- and p-GaN layers. Structures with both Mg-doped and undoped quantum wells (active regions) were deposited. Mesa type LED structures were then fabricated using Ti-Al and Ni-Au for the n-and p-ohmic contacts. Light emission was observed in a vertical cavity geometry from the sapphire or the spinel substrate side. For 250 mm diameter mesa devices the series resistances ranged from 10 to 25 Ω. These are some of the lowest reported values. Spectral emission linewidths (FWHM) of 12, 25 and 40 nm were obtained respectively for the UV, blue, and green MQW LEDs. These linewidths are similar to those of Nakamura et al. We also report on optically pumped MQW InGaN-GaN lasers with different quantum well thicknesses. In these devices, we observed the quantum shift related to the subband energy dependence on the well thickness and estimated the effective conduction band discontinuity at the GaN-InGaN heterointerface from these data.}, number={1-3}, journal={MATERIALS SCIENCE AND ENGINEERING B-SOLID STATE MATERIALS FOR ADVANCED TECHNOLOGY}, author={Khan, MA and Chen, Q and Yang, J and Sun, CJ and Lim, B and Temkin, H and Schetzina, J and Shur, MS}, year={1997}, month={Jan}, pages={265–268} }