Effect of tensile properties mismatch on fracture driving force in sandwich plates using notched specimens

This paper studies the effect of tensile properties mismatch on fracture driving force in sandwich plates using Double Edge Notched Tension (DENT) specimens. Notched specimens are used due to the difficulty in fatigue pre-cracking small sized specimens of sandwich plates. Two sandwich plates, SP1 and SP2, composed of different aluminum alloys layers are studied. AA6061 is used as cladding material in both cases while AA2017 and Al 1100 are used as core materials for SP1 and SP2, respectively. Homogenous specimens made of AA6061 are also studied for comparison. The critical fracture load is determined experimentally. Finite element elastic-plastic analysis is performed to evaluate the effect of tensile properties mismatch on fracture driving force ahead of notch tip, Jtip.The results showed that tensile properties mismatch between sandwich plate layers affects Jtip values. In case of SP1, the notch tip is shielded from the remote loading where Jtip is smaller than the remote one vice versa in case of SP2 where Jtip is amplified. It is demonstrated that the amount of shielding is normally less than amplification. In the meantime, notch depth plays an important role in the fracture process while effect of the studied notch radius is minor. Keywords: Sandwich, Mismatch, Shielding, Amplification, Notch, Fractur

Hysterographic study of pregnancies with copper intra uterine devices

IDRC supported. Hysterographic study of the contraceptive efficacy of copper intrauterine devices - examines cases of pregnancy with the copper device and concludes that the size and shape of the IUD must conform with that of the uterine cavity to prevent unintended pregnancy and side effects such as bleeding. Statistical data, bibliography

Neutron irradiation embrittlement of reactor pressure vessel steel 20 MnMoNi55 weld

SIGLECopy held by FIZ Karlsruhe; available from UB/TIB Hannover / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

Immunomodulatory effect of propofol versus sevoflurane in patients undergoing thoracic surgery using one lung ventilation technique

Introduction: One lung ventilation (OLV) has become a standard procedure for many interventions in thoracic surgery with a need for deflation of the lung to facilitate the surgical procedure. Mechanical ventilation can induce a proinflammatory reaction in the non-deflated ventilated lung. However only limited data exist on inflammatory alterations in the temporarily deflated, non-ventilated lung in patients undergoing thoracic surgery. Aim of the work: The aim of this work is to compare between the effects of propofol and sevoflurane as regards: the systemic inflammatory response, the pulmonary inflammatory response, C-reactive protein, leucocyte count, and recovery status, in patients undergoing thoracic surgery using OLV technique. Patients and methods: This study include 40 adult patients, who were randomly classified into two groups: group (I) 20 patients received total intravenous anesthesia with propofol. Group (II) 20 patients received inhalational anesthesia with sevoflurane. Every patient was subjected to a careful pre-anaesthetic assessment, anaesthesia, bronchoalveolar lavage (BAL) analysis for human inflammatory mediators (IL-6 and TNF-α), serum analysis for systemic inflammatory mediators (IL-6 and TNF-α) (Both were measured before OLV and 15 min after OLV ended and resumption of two lung ventilation (TLV) at the end of surgery, and C-reactive protein and leukocyte count in blood (before OLV, 15 min after OLV ended and resumption of (TLV) at the end of surgery and on the 2nd postoperative day). Results: According to IL-6 and TNF-α, there was no statistically significant difference between the two groups before OLV, however they were significantly increased in both groups in serum and BAL after OLV in relation to before OLV with significant increase in group I relative to group II. A significant correlation was present between increased level of IL-6 and TNF-α in BAL and their levels in serum after OLV in the group II but this correlation was not present in the group I. Also no significant correlation between duration of OLV and inflammatory mediators (IL-6 and TNF-α) in serum and BAL in both groups. As regarding to CRP, there was no statistically significant difference between the two groups before OLV. After OLV and on the 2nd postoperative day the level of CRP increased significantly in both groups with significant increase in group I relative group II. According to WBC count there was no statistically significant difference between the two groups as regards the level of WBC before OLV. After OLV the level of WBC increased significantly in group I only. On the 2nd postoperative day the level of WBC increased significantly in both groups with significant increase in group I relative to group II. Also no significant correlation between duration of OLV with the increased levels of CRP and WBC count in both groups. Conclusion: Propofol increased pulmonary and systemic cytokine release more than sevoflurane during OLV. Propofol has increased CRP level and WBC count more than sevoflurane during OLV

Epidemiological study of induced abortion by pregnancy screening in a rural community in Egypt, 1972-1973

IDRC supported. Epidemiologycal study of induced abortion in Al Kharkania village in Egypt by pregnancy screening - discusses information obtained from surveys on demographic characteristics, fertility, marital status, fecundity, menstruation, attitudes; detection of early pregnancies and abortions. Includes statistical data

Irradiation embrittlement of pressure vessel steels Analysis of IAEA coordinated programme results

With 9 figs.SIGLECopy held by FIZ Karlsruhe; available from UB/TIB Hannover / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman