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In spite of the great strides that have been made in recent years in improving Mexico’s transportation and communication systems, obtaining material through interlibrary loan is still often difficult. Focuses on two relatively small but successful programs that have been organized by the Grupo Amigos and the Transborder Library Forum (Foro). Both programs are important due to their international focus, but the latter program is particularly interesting due to changes that are being made at the Mexican coordinating library to allow end users to prepare their own ILL requests via the library’s Web page. Compares the two programs and speculates on the future of interlibrary loan in Mexico.

Donor-conceived (DC) offspring raised in lesbian-parent and heterosexual-parent families have different historical chronologies, which are clusters of events that provide frameworks for shaping contemporary views of sperm donors and donor siblings. Using surveys collected by the Donor Sibling Registry (DSR), the largest U.S. web-based registry, we found that DC offspring from different family forms have somewhat different views about meeting both the donor and donor siblings. In general, all offspring are curious about the donor. All offspring want to know what the donor looks like and they believe that even minimal contact will help them understand themselves better. However, when compared to offspring from heterosexual-parent families, offspring from lesbian-parent families are less likely to want to have contact with the donor. For offspring from lesbian-parent families, donor conception is considered a normal and accepted part of family life and the donor is deemed irrelevant to the family’s construction. Especially among those who live with two heterosexual parents (where both parents are often assumed to be genetic relatives), offspring want to know the donor because they believe he holds the key to important information that the legal (or social) father cannot provide. Most DC offspring want to meet donor siblings although the interest is somewhat weaker among the offspring in lesbian-parent families. Offspring regard donor siblings as special relations who will not disrupt the natal family and who might even become part of a new kind of “extended family” network.

The purpose of this paper is to show a possibility to measure a change of a contact angle during the melting in real-time and to reveal significant factors of a wettability. Influence of the flux with combination of plasma on copper surface was investigated in experiment as well.

Laboratory equipment consists of heating and optical part that was developed and tested for real-time contact angle’s measurements. Solder balls based on Sn96.5/Ag3/Cu0.5 and Sn63Pb37 spread out on a copper substrate during a melting process. The wettability of pure copper surface was compared with copper surface treated with flux or combination plasma–flux. The contact angle and spreading rate of a melted solder balls observed by the charged-coupled device camera were analyzed in real-time and measured using the JavaScript.

Laboratory equipment allows for analysis of contact angle and spreading rate in real-time during the melting process. The contact angle decreases more noticeable after applying the plasma-flux treatment in contrast to no flux or flux treatment only. Using the plasma treatment before application of the flux improves the wettability and the effectivity of the flux activity on the copper surface during the melting process.

The interpretation of the results of such a comprehensive measurement leads to a better understanding of the mutual relation between flux and combination plasma–flux of the wetting during the melting process. The simple, cheap, fast and accurate laboratory equipment, which consists of the heating and the optical part, allows for the wettability evaluation of the melting process in real-time.

The purpose of this paper is to study the solder beading phenomenon (referring to larger-sized solder balls) of surface-mounted electrolytic capacitors. Solder beading could induce failures by violating the minimal electrical clearance on the printed circuit board (PCB). In modern lead-free reflow soldering, especially in high-reliability industries, such as automotive, aeroplane and aerospace, detecting and preventing such defects is essential in reliable and cost-effective manufacturing.

The large size of the involved components may block the view of automatic optical inspection; therefore, X-ray inspection is necessary. To detect the failure mode, X-ray imaging, cross-section grinding, optical microscopy and Fourier transformed infrared spectroscopy were used. High-resolution noncontact profilometry and optical microscopy were used to analyse component designs. The surface mounting process steps were also analysed to reveal their dependence on the issue. Test methods were designed and performed to reveal the behaviour of the solder paste (SP) during the reflow soldering process and to emphasise the component design relevance.

It was found that the reduction of SP volume only reduces the failure rate but does not solve the problem. Results show that excessive component placement pressure could induce solder beading. Statistical analysis revealed that differences between distinct components had the highest effect on the solder beading rate. Design aspects of solder beading-prone components were identified and discussed as the primary source of the problem.

The findings can be applied in surface-mount technology production, where the total failure count and resulting failure costs could be reduced according to the findings.

This paper shows that component design aspects such as the low distance between the underside of the component and the PCB and blocked proper outgassing of volatile compounds of the SP can be root causes of solder beading under surface-mounted electrolytic capacitors.