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排序方式: 共有518条查询结果,搜索用时 15 毫秒
61.
Pyrolysis enables to recover metals and organic feedstock from waste conglomerates such as: automotive shredder residue (ASR). ASR as well as its pyrolysis solid products, is a morphologically and chemically varied mixture, containing mineral materials, including hazardous heavy metals. The aim of the work is to generate fundamental knowledge on the conversion of the organic residues of the solid products after ASR's microwave pyrolysis, treated at various temperatures and with two different types of gasifying agent: pure steam or 3% (v/v) of oxygen. The research is conducted using a lab-scale, plug-flow gasifier, with an integrated scale for analysing mass loss changes over time of experiment, serving as macro TG at 950, 850 and 760 °C. The reaction rate of char decomposition was investigated, based on carbon conversion during gasification and pyrolysis stage. It was found in both fractions that char conversion rate decreases with the rise of external gas temperature, regardless of the gasifying agent. No significant differences between the reaction rates undergoing with steam and oxygen for char decomposition has been observed. This abnormal char behaviour might have been caused by the inhibiting effects of ash, especially alkali metals on char activity or due to deformation of char structure during microwave heating. 相似文献
62.
Wiesław Barnat Pawel Dziewulski Tadeusz Niezgoda Robert Panowicz 《Computational Materials Science》2011,50(4):1233-1237
The sleeve, conical simple composite elements and polymer foam filled composite conical element behaviour during failure are presented and discussed. The impact energy in these elements is absorbed in progressive fracture process. Possibilities of energy absorption panels – the great structures made from simple elements in a certain military and civilian field are demonstrated. 相似文献
63.
Alberto J. Granero Pawel Wagner Klaudia Wagner Joselito M. Razal Gordon G. Wallace Marc in het Panhuis 《Advanced functional materials》2011,21(5):955-962
Poly(styrene‐β‐isobutylene‐β‐styrene)‐poly(3‐hexylthiophene) (SIBS‐P3HT) conducting composite fibers are successfully produced using a continuous flow approach. Composite fibers are stiffer than SIBS fibers and able to withstand strains of up 975% before breaking. These composite fibers exhibit interesting reversible mechanical and electrical characteristics, which are applied to demonstrate their strain gauging capabilities. This will facilitate their potential applications in strain sensing or elastic electrodes. Here, the fabrication and characterization of highly stretchable electrically conducting SIBS‐P3HT fibers using a solvent/non‐solvent wet‐spinning technique is reported. This fabrication method combines the processability of conducting SIBS‐P3HT blends with wet‐spinning, resulting in fibers that could be easily spun up to several meters long. The resulting composite fiber materials exhibit an increased stiffness (higher Young’s modulus) but lower ductility compared to SIBS fibers. The fibers’ reversible mechanical and electrical characteristics are applied to demonstrate their strain gauging capabilities. 相似文献
64.
Pawel E. Malinowski Atsushi Nakamura Dimitri Janssen Yoshitaka Kamochi Ichiro Koyama Yu Iwai Anna Stefaniuk Ewelina Wilenska Caterin Salas Redondo David Cheyns Soeren Steudel Paul Heremans 《Organic Electronics》2014,15(10):2355-2359
We report on the fabrication of organic photodetectors (OPD) based on isolated islands of P3HT:PCBM. Pattern transfer to the active material was done with photolithography based on non-fluorinated solvents and the excessive organic semiconductor was removed with oxygen plasma reactive ion etching. The photoresist system used was found to be benign to the P3HT:PCBM layer as confirmed by absorption, thickness and roughness measurements. Current–voltage characteristics and external quantum efficiency (EQE) remained unchanged after the patterning process. It was demonstrated that it is possible to photolithographically pattern isolated islands with 200 μm edge length with the same dark current density (<10−5 A/cm2 at −2 V bias voltage) and photocurrent density (>5 × 10−3 A/cm2 at −2 V). Furthermore, concerning the solar cell performance, the patterned, small-area devices showed power conversion efficiency of 2.1% and fill-factor of 60%. Dark current was observed to depend on the size of the remaining semiconductor island, which was demonstrated on OPDs with diameter of 50 μm. The presented results show the feasibility of fabrication of isolated devices based on organic semiconductors patterned with non-fluorinated photolithography. 相似文献
65.
Biological dosimeters are useful for epidemiologic risk assessment in populations exposed to catastrophic nuclear events and as a means of validating physical dosimetry in radiation workers. Application requires knowledge of the magnitude of uncertainty in the biological dose estimates and an understanding of potential statistical pitfalls arising from their use. This paper describes the statistical aspects of biological dosimetry in general and presents a detailed analysis in the specific case of dosimetry for risk assessment using stable chromosome aberration frequency. Biological dose estimates may be obtained from a dose-response curve, but negative estimates can result and adjustment must be made for regression bias due to imprecise estimation when the estimates are used in regression analyses. Posterior-mean estimates, derived as the mean of the distribution of true doses compatible with a given value of the biological endpoint, have several desirable properties: they are nonnegative, less sensitive to extreme skewness in the true dose distribution, and implicitly adjusted to avoid regression bias. The methods necessitate approximating the true-dose distribution in the population in which biological dosimetry is being applied, which calls for careful consideration of this distribution through other information. An important question addressed here is to what extent the methods are robust to misspecification of this distribution, because in many applications of biological dosimetry it cannot be characterized well. The findings suggest that dosimetry based solely on stable chromosome aberration frequency may be useful for population-based risk assessment. 相似文献
66.
67.
H. Hendrickx, J. De Houwer, F. Baeyens, P. Eelen, and E. Van Avermaet (see record 1997-02349-012) reported a series of (mostly unsuccessful) studies on nonconscious hidden covariation detection (HCD); for example, they reported that out of 3 attempts to replicate P. Lewicki et al.'s studies (1986, see also records 73-13630, 77-29976 and 09019, and 79-38878) only 1 produced the expected results. They concluded that HCD may be not as general and robust as the previous research suggested, and they considered boundary conditions. In this article, the authors discuss a number of weaknesses of H. Hendrickx et al.'s experiments (and systematic deviations from the original methodology) that are potentially responsible for the lack of the expected results and discuss missing facts in their arguments (e.g., they failed to mention any published replications of the HCD studies from other than the present authors' laboratories). It is argued that when all evidence is considered, the proper conclusion is that nonconscious processing of covariations is not only general and robust but also a ubiquitous phenomenon mediating a variety of processes of acquisition of information. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
68.
M Reck B Haering G Koschel E Kaukel J von Pawel U Gatzemeier 《Canadian Metallurgical Quarterly》1998,52(10):570-573
In the palliative treatment of advanced SCLC and NSCLC there is a big need for effective and well tolerable drugs. Bendamustin is an alcylatic agent which had shown activity in the treatment of Non Hodgkin- and Hodgkin-Lymphoma as well as in the treatment of solid tumors like Mamma-Carcinoma and Colorectal-Carcinoma. We treated 21 patients with NSCLC (5 pat. Stad. III b, 16 pat. Stad. IV) and 22 pat. with Extensive Disease SCLC with Bendamustin 70 mg/m2 i.v., day 1-4 (q.28 days). We observed a response rate of 40.9% in the patients with SCLC (9 PR/40.9%), (0 CR) and no response in the patients with NSCLC. Hematologic toxicity in both groups was mild (Leucopenia WHO 1 + 2: 13 pat./30.2%, WHO 3: 2 pat./4.6%; Anemia WHO 1 + 2: 13 pat./30.2%, WHO 3: 1 pat./2.4%; Thrombopenia WHO 1 + 2: 4 pat./9.6%, WHO 3: 1/2.4%). Non Hematologic toxicity consisting of Nausea/Vomiting (WHO 2 + 3:13 pat./30.2%), Diarrhea (WHO 2 + 3:3 pat./7%), Obstipation (WHO 1 + 2: 2 pat./4.6%), Fever (WHO 1 + 2: 9 pat./20.9%) and Alopecia (WHO 1 + 2: 13 pat./31.7%, WHO 3: 1 pat./2.4%) was well tolerable. Cardiac Arrhythmias occurred in 7 pat./16.3% and PNP in 2 pat./4.6%. Treatment had to be stopped in one patient because of an allergic skin reaction. Bendamustin is a well tolerable cytostatic drug with a remarkable activity in advanced SCLC which is comparable to other well known agents in the treatment of this disease. Because of the good toxicity profile a combination with other compounds might be feasible. In advanced NSCLC Bendamustin showed no activity. 相似文献
69.
Jastreboff Pawel J.; Brennan James F.; Coleman John K.; Sasaki Clarence T. 《Canadian Metallurgical Quarterly》1988,102(6):811
To measure tinnitus induced by sodium salicylate injections, 84 rats were used in a conditioned suppression paradigm. In Exp 1, Ss were trained with a conditioned stimulus/stimuli (CS) consisting of the offset of a continuous background noise. One group began salicylate injections before Pavlovian training, a 2nd group started injections after training, and a control group received daily saline injections. Resistance to extinction was profound when injections started before training but minimal when initiated after training, suggesting that salicylate-induced effects acquired differential conditioned value. In Exp 2, salicylate treatments were mimicked by substituting a 7 kHz tone in place of respective injections, resulting in effects equivalent to salicylate-induced behavior. A 3rd experiment included a 3 kHz CS, and again replicated the salicylate findings. In Exp 4, we decreased the motivational level, and the sequential relation between salicylate-induced effects and suppression training was retained. Findings support the demonstration of phantom auditory sensations in animals. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献