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41.
42.
This paper reports on statistics concerning production and consumption of packaging (as a whole or per capita) in Europe, in the USA, in Japan and in the world. Data have been provided by National Trade Associations and by consultants specialized in packaging and in economics. It is estimated that in 1986 the global consumption of packaging reached 150 millions of tonnes valued at 1200 billions of French francs. Consumption could reach 247 million tonnes by the year 2000. Paper and board have the highest consumption rate, but plastics have the highest rate of growth. Nevertheless, consumption per capita in the industrialized countries will be more than 10 times the consumption in underdeveloped countries. The packaging industries take fourth place in the USA, sixth in Western Germany and twelfth in France. In Europe, as in the world, paper and board is the material most used (40%), with glass (a high density material) taking second place and plastics third, i.e. if we consider the quantity of materials and not their value. Some differences appear between the various countries, but the figures for USA and Japan lead to similar conclusions. The survey shows clearly that the USA as compared with Europe has twice the consumption of packaging materials per capita and this difference is even greater compared with the rest of the world. 相似文献
43.
JL Michel Y Revillon P Montupet F Sauvat S Sarnacki N Sayegh C N-Fekete 《Canadian Metallurgical Quarterly》1998,33(12):1745-1748
BACKGROUND/PURPOSE: The development of thoracoscopic surgery has made many procedures possible, including the treatment of mediastinal cysts in children. The authors report their experience with this procedure between 1992 and 1997. METHODS: Surgery was performed on 22 children aged from 1 month to 9 years (median, 27 months), weighing 5 to 49 kg (median, 12.5 kg). Diagnosis was made by antenatal ultrasound scan in six cases (27%), with a chest x-ray performed for respiratory symptoms in 14 cases, and with a chest x-ray performed for positive tuberculin intradermoreaction in two cases. Decision to resect the cyst was determined by thoracoscopy in 21 of the 22 cases, and by open surgery in one case only (subcarinal compressive cyst with left lung distension and a mediastinal shift). RESULTS: Eighteen of the 21 (86%) cases were treated successfully by thoracoscopy. In three cases of bronchogenic cysts, we performed an associated thoracotomy because the dissection was too difficult and dangerous. In three cases, a small part of a common wall between the cyst and the bronchus was not removed. The pathological diagnosis was bronchogenic cysts in 15 cases (71%), pleuropericardiat cysts in three cases (14%), esophageal duplication in two cases (10%), and cystic hygroma in one case (5%). Two postoperative complications were observed: one esophageal wound and a case of recurrent pneumothorax after chest tube removal. Patients were discharged after 2 to 11 days (median, 3 days). Follow-up was uneventful. CONCLUSIONS: Treatment of mediastinal cyst by thoracoscopy is feasible in most cases. Compressive cysts with lung distension and mediastinal shift remain a contraindication. If the cysts have a common wall with the bronchus or esophagus, or if they are subcarinal, the dissection may be difficult and dangerous, and thoracotomy may be preferable. 相似文献
44.
A nonlinear regeneration pulsed oscillator driven by a monochromatic source has been built. Subharmonics of the resonance carrier/modulation are measured with an accuracy of 10-10 thanks to the use of a double beats measurement set-up. The multiscale analysis of frequency readings reveals a rich fine structure which is in agreement with the nonlinear topological approach of synchronized states. 相似文献
45.
46.
Neuropeptide Y (NPY) is a unique modulator of renal function that enhances urine flow and sodium excretion despite marked reductions in renal blood flow. We investigated whether the cyclooxygenase inhibitor indomethacin alters the renal NPY effects in anesthetized rats. Treatment with 5 mg/kg indomethacin i.p. lowered urinary prostaglandin excretion by approximately 85%. Systemic infusion of NPY elevated mean arterial pressure by approximately 15 mm Hg and renovascular resistance by approximately 8.0 mm Hg/ml/min, whereas the related peptide YY3-36 (PYY3-36) did not. Nevertheless, both peptides enhanced urine flow rate by approximately 250 and approximately 100 microl/15 min, respectively, and sodium excretion by approximately 15 micromol/15 min. Treatment with indomethacin did not affect NPY- and PYY3-36-induced alterations of systemic and renovascular hemodynamics but completely abolished NPY- and PYY3-36-induced diuresis and natriuresis. Endogenous creatinine clearance was not affected by any treatment. We conclude that cyclooxygenase-derived arachidonic acid metabolites are not involved in the systemic or renal hemodynamic effects of NPY and PYY3-36 but mediate NPY- and PYY3-36-induced diuresis and natriuresis. 相似文献
47.
We describe the case of a young woman with pain on turning her head attributable to a malformation of the hyoid bone. Diagnosis was established using spiral computed tomography with the patient's neck in the position of greatest discomfort and with 3-dimensional reconstruction of the hyoid bone. Prior conventional radiography and magnetic resonance imaging did not aid in finding a diagnosis. After surgical removal of both greater cornua of the hyoid bone there was a complete relief of symptoms. 相似文献
48.
Michel Brusin 《Materials and Structures》1990,23(2):79-80
Editorial
All a RILEM technical recommendation should be 相似文献49.
E. A. Fitzgerald Y. -H. Xie D. Brasen M. L. Green J. Michel P. E. Freeland B. E. Weir 《Journal of Electronic Materials》1990,19(9):949-955
We have grown Ge x Si1-x (0 <x < 0.20,1000–3000Å thick) on small growth areas etched in the Si substrate. Layers were grown using both molecular beam epitaxy (MBE) at 550° C and rapid thermal chemical vapor deposition (RTCVD) at 900° C. Electron beam induced current images (EBIC) (as well as defect etches and transmission electron microscopy) show that 2800Å-thick, MBE Ge0.19Si0.81 on 70-μm-wide mesas have zerothreading and nearly zero misfit dislocations. The Ge0.19Si{0.81} grown on unpatterned, large areas is heavily dislocated. It is also evident from the images that heterogeneous nucleation of misfit dislocations is dominant in this composition range. 1000Å-thick, RTCVD Ge0.14Si0.86 films deposited on 70 μm-wide mesas are also nearly dislocation-free as shown by EBIC, whereas unpatterned areas are more heavily dislocated. Thus, despite the high growth temperatures, only heterogeneous nucleation of misfit dislocations occurs and patterning is still effective. Photoluminescence spectra from arrays of GeSi on Si mesas show that even when the interface dislocation density on the mesas is high, growth on small areas results in a lower dislocation density than growth on large areas. 相似文献
50.
Benjamin Gerard Harouna Souley Ali Michel Zasadzinski Mohamed Darouach 《International Journal of Control, Automation and Systems》2012,10(6):1086-1095
This paper deals with the H ?? filtering problem for a class of nonlinear systems. This class of nonlinear systems is composed of a bilinear part and of a lipschitzian one. The use of an unbiasedness condition for the bilinear part (called quasi unbiasedness condition) permits to parameterize the filter matrices through a single gain. Two LPV (Linear Parameter Varying) extensions of the bounded real lemma are used to solve the filtering problem. This approach reduces the conservatism inherent to the boundedness of the inputs. Then the filtering solution is expressed in terms of LMI (Linear Matrix Inequality) to be verified at the vertices of a polytope. A numerical example is finally given to illustrate our approach. 相似文献