This paper demonstrates extremely efficient (η(P,max) = 118 lm W(-1) ) ITO-free green phosphorescent OLEDs (PHOLEDs) with multilayered, highly conductive poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) (PEDOT:PSS) films as the anode. The efficiency is obtained without any outcoupling-enhancing structures and is 44% higher than the 82 lm W(-1) of similar optimized ITO-anode PHOLEDs. Detailed simulations show that this improvement is due largely to the intrinsically enhanced outcoupling that results from a weak microcavity effect.

We report on the measurement of fundamental properties such as deep defects and hole mobility in poly-3-hexyl-thiophene (P3HT)/[6,6]-phenyl-C60-butyric acid methyl ester(PCBM) solar cells when the cells are exposed to solar radiation without any atmospheric exposure. It is found that the midgap defect density in P3HT and the interface density between P3HT and PCBM increase significantly upon light soaking along with a reduction in hole mobility in P3HT. The increase in defect density leads to a corresponding increase in reverse saturation current of the diode, and the corresponding decrease in open circuit voltage of the cell upon light soaking.

No abstract

Ideally, the sawmill manager knows what he/she should pay for each sawlog and what profit to expect from each log of a given species, diameter, length, grade, and quality. In reality, hardwood sawmill managers seldom base sawlog prices on the log's profit potential. Rather, they tend to base raw material price on what they must pay to compete with those seeking the same material. In many cases, logs are processed at severe losses. The conventional sawmill study typically has been conducted on a substantially similar "batch" of logs to gain insight into gross (volume) yield, grade yield, and profitability for those logs. Traditional mill studies capture data over an abbreviated time span of only a day or two. Instead, mill study data should be collected continuously so that the results reflect potential profitability for a broad range of operating conditions. Alternate study approaches and specific mill study jobs are described and tools are provided for conducting sawmill studies. In today's global economy, the opportunity cost associated with suboptimal utilization of raw material and mill resources is substantial. As a result, understanding the profit potential associated with different types of logs is critically important for sawmill survival. The AuthorsROBERT MAYER is a consulting forester and sawmill specialist in Indiana. He formerly was vice president of operations for a major hardwood sawmill. JAN WIEDENBECK is a Project Leader and research scientist with the USDA Forest Service's Northeastern Research Station at Princeton, West Virginia.

THIS book is so well known that little need be said here to describe its contents and philosophy. In this second edition sections on root loci and analog computers have been added, and some reorganization and extension have taken place in the sections relating to Bode plots and error coefficients-the latter with an unfortunate typographical omission of a complete line of text.