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排序方式: 共有1765条查询结果,搜索用时 4 毫秒
1.
Elisabeth Gehrer 《e & i Elektrotechnik und Informationstechnik》2002,119(7-8):220-220
2.
Two different generators for ozone were tested, a traditional electrical discharge generator and a generator based upon UV–irradiation of air at 150–180 nm. It was demonstrated that the traditional generator gave slightly higher reductions in levels of color for equivalent ozone dosages. Both gases affected the molecular weight distribution in the way that the bigger molecules were broken down to smaller ones. No significant difference between the molecular weight reduction efficiency of the gases was found. 相似文献
3.
Four intervention models that aim to reduce problematic caregiver–infant relationships are reviewed within the context of attachment theory. These models include support, guidance, psychotherapy, and infant-led psychotherapy. All of the models are consistent with attachment theory in that they aim to enhance maternal sensitivity and responsiveness. Only infant-led psychotherapy focuses primarily on the mother–infant relationship and directly includes the infant in treatment instead of focusing and working primarily with the more verbal partner, the caregiver. Thus, of the 4 interventions, infant-led psychotherapy is most consistent with the current empirical and theoretical understanding of infants as active contributors to their relationships and development. However, there is little empirical research on this intervention; the bulk of studies evaluate support and guidance. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
4.
The dissociative chemisorption of methane on a Ni(100) single crystal has been studied under thermal conditions as a function of pressure and temperature. The initial sticking coefficient was measured in the pressure range of 0.010–7.0 mbar at temperatures ranging from 375 to 500 K. A strong pressure dependence was observed, consistent with a direct dissociation mechanism under these thermal conditions. This was further confirmed by experiments where the gas at a low pressure was heated by a thermal finger facing the crystal surface. With the thermal finger at the same temperature as the surface, it was possible to ensure that the methane was fully equilibrated to the crystal and an activation energy of 59±1.5 kJ/mol was determined under isothermal conditions. 相似文献
5.
The kinetics of aluminium deposition from NaCl-AlCl3 melts (cAlCl3 < 10 mol%) contained in alumina crucibles was studied by linear sweep voltammetry and potential step amperometry at temperatures around 820°C. At low concentrations (cAlCl3 < 0.4 mol%) the reduction of AlCl3 on liquid aluminium has been found to be diffusion controlled. At higher concentrations a passivation of the aluminium electrode was observed during the deposition reaction. The passivation appears to be caused by precipitation of alumina from supersaturated melt in the diffusion layer at the aluminium cathode. 相似文献
6.
A layer-type complex TaS2 (α-naphthylamine)0.46 having a basal spacing of 2.2 nm was prepared by soaking a mixture of the components in an ampoule at 433 K for 25 to 35 days. This complex was resealed in an ampoule after purification, followed by γ-radiation and heating to 473 K. The resulting sample was again heated at various temperatures below 1273 K. On heating to 643 K, the insertedα-naphthylamine polymerized, although with some removal from the complex, with a decrease in basal spacing to 1.35 nm. Another complex appeared faintly simultaneously. This second complex with a basal spacing of 0.96 to 0.92nm formed more abundantly on heating to 773 K and then decreased in amount at higher temperature. The complex decomposed at1273 K to result in TaS2. Such thermal degradation behaviour is discussed from the standpoint of preparation of the layer-type complex consisting of TaS2 and carbon. 相似文献
7.
Eugen Seel Elisabeth Zeeb und Karl Reihling 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1919,37(1-2):1-17
Zusammenfassung Die Ergebnisse der chemischen Untersuchung von Fleisch- und Wurstwaren sind als ausschließliche Grundlage für ihre Beurteilung durchaus ungenügend; denn wir können noch nicht annähernd sämtliche chemischen Einzelbestandteile des Fleisches und der Wurstwaren mittels der im praktischen Laboratorium anwend aren Methoden nachweisen und noch viel weniger diese Einzelbestandteile quantitativ ermitteln. Es läßt sich aber auch im allgemeinen durch die chemische Untersuchung allein nicht feststellen, ob eine unter bestimmten Namen in den Handel gebrachte Ware die in diesem Namen zum Ausdruck gebrachten Fleischbestandteile tatsächlich enthält, wie z. B., ob Leberwurst Leber enthält, ferner ob minderwertige oder verbotene Organund Gewebeteile beigemischt sind oder nicht.Daher ist die mikroskopische Untersuchung, besonders in gerichtlichen Fällen, unerläßlich.Die nur auf mikroskopischem Wege erreichbare Kenntnis der in Fleisch und Wurstwaren enthaltenen Gewebe und Organe erleichtert bezw. ermöglicht die Beurteilung von Fleisch- und Wurstwaren nicht nur in vorgenannter Richtung, sondern sie erleichtert auch sehr wesentlich die Beurteilung ihres Gesamtwertes. Dieser ist verschieden je nach dem Vorhandensein der mikroskopisch nachzuweisenden Gewebe bezw. Organe und nach deren Wassergehalt. Letzterer wiederum ist z. B. bei Muskelfleisch konstanter und liegt in engeren Grenzen als bei den drüsigen Organen; im elastischen Bindegewebe ist er bedeutend niedriger als im kollagenen Bindegewebe oder im Muskelfleisch.In der vorliegenden Arbeit ist der Versuch gemacht, die mikroskopischen Schnitte der wichtigsten in Betracht kommenden Gewebe und Organe in gekochtem Zustande so zu charakterisieren, daß sie in Gemischen einwandfrei identifiziert werden können.Die Technik der mikroskopischen Untersuchung von Fleisch- und Wurstwaren ist unter Angabe bewährter Verfahren eingehend dargestellt. 相似文献
8.
9.
Eleni Koliakou Manthou Maria Eleni Ioanna Koumentakou Nikolaos Bikiaris Polyanthi Konstantinidou Patricia Rousselle Doxakis Anestakis Elisabeth Lazaridou Evangelia Kalloniati Dimosthenis Miliaras Anna Michopoulou 《International journal of molecular sciences》2022,23(12)
Syndecans act as independent co-receptors to exert biological activities and their altered function is associated with many pathophysiological conditions. Here, syndecan-1 and -4 were examined in lesional skin of patients with psoriasis. Immunohistochemical staining confirmed altered syndecan-1 distribution and revealed absence of syndecan-4 expression in the epidermis. Fibronectin (FN)—known to influence inflammation and keratinocyte hyperproliferation via α5β1 integrin in psoriasis—was also decreased. Syndecan-1 and -4 expression was analyzed in freshly isolated lesional psoriatic human keratinocytes (PHK) characterized based on their proliferation and differentiation properties. mRNA levels of syndecan-1 were similar between healthy and PHK, while syndecan-4 was significantly decreased. Cell growth and release of the pro-inflammatory Tumor Necrosis Factor-alpha (TNFα) were selectively and significantly induced in PHKs plated on FN. Results from co-culture of healthy keratinocytes and psoriatic fibroblasts led to the speculation that at least one factor released by fibroblasts down-regulate syndecan-1 expression in PHK plated on FN. To assay if biological treatments for psoriasis target keratinocyte proliferation, gelatin-based patches enriched with inteleukin (IL)-17α or TNFα blockers were prepared and tested using a full-thickness healthy epidermal model (Phenion®). Immunohistochemistry analysis showed that both blockers impacted the localisation of syndecan-1 within the refined epidermis. These results provide evidence that syndecans expression are modified in psoriasis, suggesting that they may represent markers of interest in this pathology. 相似文献
10.