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排序方式: 共有548条查询结果,搜索用时 31 毫秒
81.
P Oldenbüttel DH Antoni HJ Krieg M Engel K Wencke W Delius 《Canadian Metallurgical Quarterly》1997,86(9):732-737
A case of phlebothrombosis with recurrent pulmonary and cerebral embolism is presented which occurred in a 42 year old patient two weeks after treatment of a traumatic crural fracture despite of prophylaxis with low molecular heparin. By means of transthoracic echocardiography a large intracardiac thrombus was detected, entrapped in an patent foramen ovale (PFO) and prolapsing through both atrioventricular valves into both ventricles. This was found after systemic thrombolysis with rtPA had been performed because of fulminant pulmonary embolism. Subsequently the intracardiac thrombus was surgically removed and the PFO closed. The importance of an PFO for paradoxical embolism is discussed as well as the various therapeutical paths to treat an "embolus-in-transit" (cardiac surgery, thrombolytic therapy or anti-coagulation). 相似文献
82.
E De Antoni B Salvati R Capoano M Stracqualursi E Inches R Chiappa MP Burzacca A Bondanese FM Fiore C Frusta S Ciampini F Santoni A Costanzo A Platone T Evangelista L Zocchi 《Canadian Metallurgical Quarterly》1997,18(10):532-536
The Authors, through a review of their vascular surgery experience in the treatment of PAOD at the III General Surgery Institute directed by Prof. G. Di Matteo (University, of Rome), focus their attention on endovascular surgery. Initially considered as an effective complement to "traditional surgery" rapidly its role has grown as an effective alternative for a number of vascular patients. 相似文献
83.
Antoni Malet 《Centaurus; international magazine of the history of science and medicine》2019,61(1-2):111-132
This paper takes Franco's Spain to be a powerful case study for analyzing the ways in which power shapes science and technology and is shaped by them in return. Spain was the last country in Western Europe to establish closer links with any of the international cooperative institutions emerging after WWII. As such, developments internal to Spanish society were quite autonomous and relatively free from foreign influences. The paper focuses first on the brand new, powerful institution that the Francoist regime created to promote scientific research under tight political control, the Consejo Superior de Investigaciones Científicas. Next it turns to applied science and technology, top priorities for the regime's state‐supported programs of industrialization. They were implemented through the politically and financially powerful Instituto Nacional de Industria. Using diplomatic sources, the paper next argues that, until the late 1950s, Spain maintained substantial political and economic isolation essentially because the regime bet on autarkic policies and a model of largely isolated development. In this model, it was crucial for the regime to develop its own technological and scientific resources. Finally, the paper examines how the regime fostered a new Spanish identity in which science had a new role. 相似文献
84.
Antoni Martínez-Ballesté Hatem Rashwan Domenec Puig Agusti Solanas 《International Journal of Information Security》2018,17(3):279-290
Worldwide, thousands of video surveillance cameras record our daily activities. People are aware that video surveillance is deployed for the sake of security. However, the privacy of individuals would be endangered if the proper measures were not considered. Privacy-aware video surveillance has historically been addressed by proposals based on detecting individuals and other sensitive parts of the video and hiding them using a variety of techniques. In this paper, we present a comprehensive solution tackling video processing, video protection and management of the Information System. We claim that a video surveillance system can protect our safety and, at the same time, guarantee our privacy. We describe the design and implementation of a privacy-aware video surveillance platform that, in order to be trustworthy, accomplishes with the properties of high detection accuracy, real-time performance and protected video utility. We have tested the proposed platform, and we demonstrate the feasibility of our approach for privacy protection. 相似文献
85.
Investigations are presented on the effect of the preliminary ozonation on ultrafiltration (UF) and powdered activated carbon (PAC) /UF process performance, especially on permeate flux decline and the effectiveness of model organics removal. Flat membranes from regenerated cellulose were used. A model solution was prepared as a mixture of humic acids and phenol. PAC dosage was equal to 100 mg/l−1. The ozone dosages were in the range of 1–3 mg O3 l−1 (0.2–0.6 mg O3/mg TOC). It was found that the most advantageous configuration was preliminary ozonation with an ozone dosage of 0.4 mgO3/mg TOC–UF. The permeate flux reached a value equal to the pure water flux value. Moreover, a very high effectiveness of model organics removal was obtained: TOC was reduced by about 96% and UV254 absorbance was removed completely. When PAC was added to the feed containing humic acids without ozonation, a drop in a permeate flux was observed compared to UF. Similarly, the addition of PAC to feed treated with ozone resulted in a significant drop in the permeate flux in comparison with pure water flux, regardless of ozone dosage applied. 相似文献
86.
Studies on the effect of humic acids and phenol on adsorption-ultrafiltration process performance 总被引:6,自引:0,他引:6
Application of pressure-driven membrane processes, such as ultrafiltration (UF) and microfiltration (MF) for surface water treatment have become very popular during last decades. Membrane fouling by humic substances (HS) is one of the major limiting factors in these processes. In order to alleviate the unfavorable effects of the presence of HS in the feed on the process performance UF and MF are often combined with adsorption on powdered activated carbon (PAC). The main goal of the present study was to evaluate the effect of humic acid (HA) on membrane fouling during UF. Moreover, the effect of PAC addition to the feed on UF process, especially on flux decline was determined. The applicability of the adsorption-ultrafiltration (PAC/UF) system to purification of water containing low (phenol) and high molecular (HA) was also investigated. Three different polymer UF membranes, prepared from polysulfone (PSF), cellulose acetate (CA) or polyacrylonitrile (PAN) were applied. It was found that the membranes prepared from PSF and CA are very susceptible to fouling caused by HA. The permeate flux decreased for ca. 50% during UF of HA solution through the PSF membrane and for ca. 45%-through the CA membrane. In the case of the PAN membrane, a negligible effect of HA on the flux was observed. On the basis of the FTIR spectra it was found that the drop in the permeate flux through these membranes may result from interactions between the negatively charged functional groups present on the membrane surface, such as carboxyl groups (CA) and sulfone groups (PSF) with HA, which results in coating of the membrane surface with HA. When PAC was added to the feed containing HA, the permeate flux through the CA and PAN membranes was maintained on a practically unchanged level. However, in case of the PSF membrane, a 50% drop in the permeate flux in comparison with the flux value, when process was conducted without PAC addition was observed. That was supposed to be due to attractive forces among hydrophobic PAC particles, HA molecules and PSF membrane surface. The performed studies showed that the application of PAC/UF system was very effective in the removal of organic substances having both, low and high molecular weights. The role of PAC suspended in a feed in the PAC/UF system is the adsorption of low molecular organic compounds, which cannot be removed by UF alone. 相似文献
87.
Composite Ni-P-TiO2 and Ni-P-TiO2-Al layers were prepared by simultaneous electrodeposition of nickel and titanium dioxide (anatase) with an addition of Al. powder on a copper substrate from a solution in which TiO2 and Al powder were suspensed by stirring. The electrodeposition was carried out under galvanostatic conditions at a current density j = 300 mA cm–2 and temperature of 298 K. The phase composition of the layers was investigated by the X-ray diffraction method. It was found that during the electrodeposition process a spherical crystalline particle of TiO2 could be incorporated into the Ni-P phase matrix. The diffractogram of Ni-P-TiO2-Al layer shows that the layer contains crystallites of aluminium and TiO2. It means that transport of the metallic phase to the electrode is only possible when using TiO2 as its carrier. This allows to extract of aluminium in alkaline environment from the Ni-P-TiO2-Al layer and to obtain the active surface. 相似文献
88.
MiquelA. Perics David Castellnou Israel Rodríguez Antoni Riera Lluís Sol 《Advanced Synthesis \u0026amp; Catalysis》2003,345(12):1305-1313
A functional analogue of (R)‐2‐piperidino‐1,1,2‐triphenylethanol was synthesized and anchored to different polymeric supports by a position remote from the active region. This strategy, leading to what we call a tail‐tied ligand, allows for the achievement of the optimal transition state geometry in the catalytic process. The catalytic activity of the resulting heterogenized ligands was investigated by online FTIR analysis. The optimum polymer was assayed in the addition reaction of diethylzinc to a large family of aldehydes rendering essentially intact high catalytic activity and enantioselectivity compared to its homogeneous counterpart. 相似文献
89.
Antoni Femenia James A Robertson Keith W Waldron Robert R Selvendran 《Journal of the science of food and agriculture》1998,77(4):511-518
By-products arising from vegetable processing activities have been assessed in relation to their potential application as sources of dietary fibre supplements in refined foods. Sources used were fresh cauliflower, globe artichoke and chicory witloof. Non-starch polysaccharide (NSP) content and composition of selected parts of each plant source have been measured from alcohol insoluble residues (AIR) and by fibre analysis, complemented by methylation analysis to characterise structural features of component polysaccharides. Results indicate that cauliflower upper stem NSP was similar to the floret (∽25 g kg−1 fresh weight) and each was rich in pectic polysaccharides. Cauliflower lower stem was enriched in NSP (∽66 g kg−1) due mainly to cellulose and xylan deposition, which resulted in a proportionate decrease in pectic polysaccharides. Artichoke stem (∽38 g NSP kg−1) was similar to the receptacle (∽34 g NSP kg−1) but bracts were heavily lignified. Chicory root and leaf bud were each rich in pectic polysaccharides but NSP content was much higher in the root (∽46 g kg−1) than the leaf (∽8 g kg−1). Results indicate that processing by-products, eg cauliflower upper stem, artichoke stem and chicory root, could prove useful as sources of pectic polysaccharide-rich supplements. However, polysaccharide composition and glycosidic linkage pattern also identified important structural differences between sources. The importance of ‘fibre type’ when considering development of food supplements is discussed. © 1998 SCI. 相似文献
90.