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A strong network of partnerships is the lifeblood of the modern library system. The experience of the Gwinnett County (GA) Public Library System (GCPL) certainly supports the truth of this [...]

Georgia's Gwinnett County Public Library (GCPL) serves an extremely diverse population that speaks over 100 languages. The library rises to that challenge. 'GCPL makes every effort to match the demographic [...]

Seeing Melissa and Trent on the cover of the bride's edition (January/February) was an incredible surprise and a wonderful gift. We had no idea their picture would be chosen, and [...]

Line termination is one technique for incorporating high-speed CMOS devices into designs. Line termination eliminates impedance mismatches, thereby: increasing noise immunity; suppressing RFI-EMI; and helping to insure minimal distortions of signals. Guidelines are given to help the user decide whether to undertake the extra cost and complications involved in terminating traces on his board, and which of five termination methods best suits his application: series, parallel, Thevenin, ac, or active. Each method is evaluated in terms of power consumption, added parts, added delay, resistor value, and capacitor value.

Limit noise in designs using advanced CMOS logic As logic designers find creative techniques to reduce device-generated noise, systems designers live with this noise by employing high-performance design rules. To [...]

No rate increases should occur until 1995, but other changes are afoot. The past year has brought rapid changes to the U.S. Postal Service. The institution has never gone through [...]

READING THE ARTICLE 'FINANCIALLY PREPARED FOR LIFE' [May 2004] made me feel proud of Mrs. Nicole Simpson. Too often when black individuals (including me) are doing well financially, we forget [...]

Polybagging: What you can and can't do After two years of intense deliberation that required four Federal Register proposals, the United States Postal Service has issued its final ruling on [...]

We are writing in response to the Feb. 10 Letter from Katherine D. Moseley, deputy assistant director for the City of Houston Finance and Administration Department, addressing the Jan. 27 [...]

Several letters to the editor are presented including one in which the sender shares the successful year in their industrial art shop, another one that shares a few Reflections by Lifelong Under-the-Radal Nonprofessional Luthier, and a letter in which the sender expresses his admiration to the dedication being given by a certain Mr. Mottola to lutherie.

For many publishers, lowering distribution costs has become the key issue for the nineties. And for most, that comes down to one word: postage. Although rising postage rates are squeezing [...]

For many publishers, lowering distribution costs has become the key issue for the nineties. And for most, that comes down to one word: postage. Although rising postage rates are squeezing [...]

An inexpensive, simple (but highly automated) instrument for acquiring high-resolution fluorescence and phosphorescence spectra of polycyclic aromatic hydrocarbons (PAHs) is described. Fluorescence and phosphorescence signals are processed by gated integration and photon counting, respectively. The instrument can be used to acquire excitation as well as emission spectra in both the frequency and time domain. In addition, a method for measuring single and double exponential phosphorescence decay times is presented. Decay times ranging from 0.3 ms to 300 ms were measured for several naphthalene derivatives, with a precision of ∼10%. The primary advantages of this instrument are high sensitivity, high selectivity, wide linear dynamic ranges, and a versatile range of applications.

Aromatic hydrocarbons can be detected at subpicogram levels under conditions of high spectral resolution when the sample is placed in an aromatic crystal with molecular dimensions matched to the analyte. The advantages of using a low-temperature parent-molecule matrix have been assessed by comparing the laser-induced fluorescence and two-photon excitation of fluorescence spectra of methylnaphthalene, chloronaphthalene, and hydroxy-naphthalene derivatives in durene and naphthalene crystals. It has been demonstrated that the parent-molecule matrix is well suited for use with its derivatives and that sharp spectral features result for a wide variety of substituents and substitution positions. The vapor-deposition procedure that has been developed is characterized by high spectral resolution and good quantitative precision and is often essential for detecting subpicogram levels. The potential of two-photon excitation of fluorescence for trace analysis has also been explored.

Loose enclosures: Understanding your options Publishers are asking many questions about the use of loose enclosures: What are permissible enclosures? What regulations must publishers adhere to when they enclose loose [...]