RESUMEN
Using scanning tunneling microscopy experiments in combination with first-principles calculations we have studied the geometric structure of the compressed c(7sqrt(2) × sqrt(2)) antiphase domain structure of CO on Cu(001). We find direct evidence for structural relaxations involving an inhomogeneous CO environment characterized by molecular tilting, bending, and nonterminal sites. Our analysis solves the long-standing problem of the adsorption structure of the compressed phase and is important for understanding the physical properties of this fundamental adsorption system.
RESUMEN
Surface x-ray diffraction in combination with scanning tunneling microscopy and molecular dynamics calculations provide first quantitative evidence for unusually large relaxations in nanometer-sized Co islands deposited on Cu(001) at 170 K. These lead to sharply reduced interatomic Co distances as low as 2.36 A as compared to bulk Co (2.51 A) involving low symmetry Co adsorption sites. Our results prove the validity of the concept of mesoscopic mismatch which governs the strain relaxation of nanosized islands in general.
RESUMEN
PIP: A multicenter study with 328 women, 302 of whom were nulliparous, was carried out using a Copper 7 IUD of reduced size: the Mini-gravigard. 10 Swiss and Austrian gynecologists in private practice participated in the trial. 92% of the patients were nulliparous. Insertion was easy and painless in the majority of the cases. An experience of 3081 women cycles was accumulated. Over the 28-month study, 5 involuntary pregnancies were recorded (Pearl Index=2). The percentage of spontaneous expulsions was 4.9% (16 cases of partial or complete expulsion). In 7.6% of all women (25 cases), the device was removed due to pelvic pain and persistent bleeding. An evaluation of these results has been performed according to the life-table method.^ieng
