Memoirs on the coleoptera / by Thomas L. Casey.

7

Memoirs on the coleoptera / by Thomas L. Casey.

8

Memoirs on the coleoptera / by Thomas L. Casey.

6

Memoirs on the coleoptera / by Thomas L. Casey.

5

Memoirs on the coleoptera / by Thomas L. Casey.

3

Memoirs on the coleoptera / by Thomas L. Casey.

2

Memoirs on the coleoptera / by Thomas L. Casey.

1

Memoirs on the coleoptera / by Thomas L. Casey.

4

The fur seals and fur-seal islands of the North Pacific ocean / By David Starr Jordan, [et al.]

1

Optimisation of a surface mount technology process using a SnAgCu lead-free alloy

The impending introduction of lead-free solder in the manufacture of electrical and electronic products has presented the electronics industry with many challenges. European manufacturers must transfer from a tin-lead process to a lead-free process by July 2006 as a result of the publication of two directives from the European Parliament. Tin-lead solders have been used for mechanical and electrical connections on printed circuit boards for over fifty years and considerable process knowledge has been accumulated. Extensive literature reviews were conducted on the topic and as a result it was found there are many implications to be considered with the introduction of lead-free solder. One particular question that requires answering is; can lead-free solder be used in existing manufacturing processes? The purpose of this research is to conduct a comparative study of a tin-lead solder and a lead-free solder in two key surface mount technology (SMT) processes. The two SMT processes in question were the stencil printing process and the reflow soldering process. Unreplicated fractional factorial experimental designs were used to carry out the studies. The quality of paste deposition in terms of height and volume were the characteristics of interest in the stencil printing process. The quality of solder joints produced in the reflow soldering experiment was assessed using x-ray and cross sectional analysis. This provided qualitative data that was then uniquely scored and weighted using a method developed during the research. Nested experimental design techniques were then used to analyse the resulting quantitative data. Predictive models were developed that allowed for the optimisation of both processes. Results from both experiments show that solder joints of comparable quality to those produced using tin-lead solder can be produced using lead-free solder in current SMT processes.

Report of the State board of agriculture on the work of extermination of the gypsy moth.

1898:Jan.

The naturalist's guide in collecting and preserving objects of natural history, with a complete catalogue of the birds of the eastern Massachusetts.

[1873 printing]

Free Medical Information Doctor = Publisher

Today, doctors can be publishers – computer technology and the internet make it possible, and book projects are tempting in terms of money. A doctor who publishes his own textbooks can earn many times what he would be paid in royalties by a publishing house. More important than this, however, is the fact that a doctor who writes and publishes wants his texts to be read by as many colleagues, students and patients as possible. The best way to achieve this is through free parallel publication of these texts on the internet

Gypsy and brown-tail moth bulletins.

Bull. no. 1