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991.
992.
Cooney CM 《Environmental science & technology》1996,30(11):479A
Government. 相似文献
993.
Pantelis G. Pechlivanidis 《Creativity & Innovation Management》1993,2(3):207-212
Programmes for stimulating innovation in Small and Medium Enterprise (SMEs) in Greece have been examined. Problems of innovation development, lack of funds, and marketing have been identified. The case is followed by comments from researchers with experience of entrepreneurship in various different countries. 相似文献
994.
Two cases of female patients operated fo the tumors of the stomach are presented. Result of histologic examination was rather surprising in both cases--leiomyoma. 相似文献
995.
996.
997.
P Hourdequin L Bednarczyk R Gabriel G Harika C Quereux P Wahl 《Canadian Metallurgical Quarterly》1996,25(5):528-532
We report three cases of pulmonary edema associated with prolonged intravenous tocolytic therapy with beta 2-adrenergic agonists among patients with multiple pregnancies. Although beta 2-adrenergic agonists may have direct myocardial side-effects, the underlying pathophysiologic mechanisms are mainly noncardiogenic. The most important one appears to be the fluid overload, related to amounts of fluids given intravenously and to direct result of beta-sympathomimetic therapy on renal excretion of sodium and water. Neonatal benefit of prolonged tocolytic therapy remains hypothetical. If this strategy is used, the prevention of cardiovascular adverse effects requires an intensive maternal supervision, especially in case of multiple pregnancy, the use of beta 2-adrenergic agonists in concentrated solution in order to reduce the amounts of fluids given intravenously, and the association with progesterone therapy which can reduce the infusion rate and the duration of tocolytic therapy. 相似文献
998.
S. M. Logvinkov G. D. Semchenko S. V. Tishchenko V. I. Toshinskii V. A. Borovaya I. N. Opryshko 《Glass and Ceramics》1996,53(1-2):33-34
Compositions and technologies are suggested for preparing highly efficient catalyst blocks with a honeycomb structure to be used for reducing nitrogen oxides with ammonia in flue gases from thermal power plants. The blocks have high structural strength and catalytic activity. 相似文献
999.
This paper presents a six-year study of the use of computers in a Greek primary school, based on the premise that, in contrast to current technocentric views regarding the use of information technology in the Greek educational system, computers can be used as tools for self-enhancement. The aim of the school project was to infuse a child-centred pedagogy, through the learning of Logo programming, into the whole of the school's society, i.e. all children and all teachers. Within this context, we have identified and explored how children may learn programming through a process of forming ‘naive’ or locally applicable theorems concerning key programming ideas such as the use of primitives, structuring a problem by means of writing procedures, and constructing and working with generalised notional objects by means of defining procedures with variable inputs. We discuss the emerging interrelated educational and technological aspects concerning this kind of learning, and then set these against the challenge to exploit the developing technology further in order to design expressive media of increasing flexibility and power, and to focus on specific learning domains. 相似文献
1000.
Fractionation of partly hydrolysed polyvinyl acetate (PVA) was performed by warming of its aqueous solutions. The following properties of the obtained fractions were determined: viscosity, molecular weight and molecular weight distribution, surface tension, and absorbance in the IR range. The blockiness of the polymer molecules, characterized by their behaviour towards iodine-containing systems such as I2,-H3BO3 and I2,-KI, was estimated. Fractionation of the aqueous solutions of PVA by warming is based mainly on the different internal molecular structure of the separated products, i.e. on the length of the vinyl acetate blocks in the PVA molecules and, to a lesser extent, on the degree of hydrolysis and the degree of polymerization. The more blocklike are the PVA molecules, the less compatible are the polymers in the PVA-hydroxypropyl methylcellulose (HPMC)-water system. At phase separation in this sytem the PVA molecules which are not compatible with HPMC are, in the first place, those of the highest blockiness. 相似文献