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21.
Civil Engineer Sigurd Hveem at the Norwegian Building Research Institute, BI, describes the laboratory and field tests carried out on the dynamic response of different lightweight timber floors to establish new design guidelines. NBI are also looking at theoretical calculation methods in order to predict the results obtained by measuring dynamic properties.  相似文献   
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In order to develop future manufacturing strategies the chemical and pharmaceutical industry works on the implementation of process intensification and new modularization methods. In this paper current challenges, process intensification approaches and future manufacturing initiatives are summarized and discussed.  相似文献   
24.
This study prospectively investigated the effects of psychological hardiness, job control, and job demands on medically certified sickness absence. Data from a questionnaire survey were combined with archival data for sickness absence among 7,239 civilian and military employees of the Norwegian Armed Forces (84.3% male, 69.8% military). A 2-component hurdle regression was used in the statistical analyses of the sickness absence data. After controlling for age, sex, and baseline absence, hardiness predicted both the likelihood of having any sickness absence (odds ratio = 0.97) and the number of absence spells (a 6.5% decrease in the expected count for 1 standard deviation change in hardiness). In addition, an interaction was found among hardiness, job control, and psychological demands. When demands were high, high job control was associated with more absence among employees with low levels of hardiness. Together, these findings point to hardiness as an important individual resource in relation to health, and that it is necessary to consider individual differences when examining the effects of work characteristics. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
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Practice world     
Civil Engineer Sigurd Hveem at the Norwegian Building Research Institute, BI, describes the laboratory and field tests carried out on the dynamic response of different lightweight timber floors to establish new design guidelines. NBI are also looking at theoretical calculation methods in order to predict the results obtained by measuring dynamic properties.  相似文献   
26.
Perhydrotriphenylene‐based channel‐forming inclusion compounds (ICs) and thin films made of polyphenylenevinylene (PPV)‐type oligomers with terminal alkoxy groups are investigated and compared in a combined experimental and theoretical approach. Interchromophore interactions and host‐guest interactions are elucidated by UV/Vis and Raman spectroscopy. The impact of the local environment of the chromophore on the optical and photophysical properties is discussed in light of quantum‐chemical calculations. In stark contrast to thin films where preferential side‐by‐side orientation leads to quenching of photoluminescence (PL) via non‐emissive traps, the ICs are found to be attractive materials for opto‐electronic applications: they offer high chromophore concentrations, but at the same time behave as quasi‐isolated entities of tightly packed, well‐oriented objects with high PL quantum yields and the possibility of color tuning.  相似文献   
27.
The separating behaviour of emulsified slag is greatly influenced by the flow conditions prevailing in the ladle. Especially non-steady flow conditions characterized by a time-related decrease in flow velocity (decaying flow condition) play an important role in this context. In order to clarify these phenomena, a number of numerical computations and model trials were performed. The computed and measured results obtained show a high degree of coincidence. Specific process engineering recommendations aimed at an improvement in the separation of emulsified slag droplets are presented. A new equation has been developed to calculate the holding time required for the separation of emulsified slag droplets between the ladle filling and casting steps. The results obtained with this equation coincide accurately with the computed and measured data. In addition, model trials and numerical computations of this type may contribute to a quick and economically efficient solution of similar problems in the design and improvement of other metallurgy and process technology systems.  相似文献   
28.
The Ti–Ni–W two‐phase shape memory alloy (SMA) thin film system is presented as a prototype for new SMAs with tailorable thermal transformation hysteresis (ΔT). The concept is to combine the SMA TiNi with almost insoluble W to create the two‐phase system (TiNi)–(β‐W). This system behaves like a pseudobinary TiNi system. Phase transformation behavior for compositions above the solubility limit of W in TiNi exhibit a B2–R phase transformation with characteristically small ΔT. Moreover, ΔT is dependent on the amount of W and it can be tailored to zero and even negative. This phenomenon is rationalized as being due to the mechanical interaction between the phases B2‐TiNi and β‐W. The presented results are very promising for the development of high‐speed Ti–Ni‐based SMA actuators.  相似文献   
29.
Increasing the productivity and improving the product quality are permanent requirements in steelmaking. For this purpose also detailed information on flow conditions of the melt is required. Therefore, beside operational trials, mainly physical and mathematical modelling approaches play an important role to obtain relevant information. The present state of selected simulation approaches used at the BFI are described and their application is exemplarily shown for the alloying process in a ladle, inclusion separation in a tundish and the electromagnetic stirring in a billet mould. Detailed information on these processes was obtained and improved process engineering measures could be elaborated.  相似文献   
30.
    
Zusammenfassung Aus dem Rauch verschiedener Zigaretten werden die flüchtigen Nitrosamine durch mehrfache Clean-up-Verfahren angereichert und die nach einer säurekatalysierten Denitrosierung erhaltenen Amine zu fluorescierenden Derivaten des 7-chlor-4-nitrobenzofurazan (NBD-Cl) umgesetzt. Diese auf Polyamidfolien getrennten NBP-Amine werden fluorimetrisch mit einem Chromatogramm-Spektralphotometer quantitativ bestimmt. Es ergeben sich Wiederfindungsraten von 60–80% für die verschiedenen Nitrosamineaus Zigarettenrauchkondensat. Quantitativbestimmt wurden die Nitrosamine N-Nitrosodimethylamin, N-Nitrosodiäthylamin, N-Nitrosopiperidin, N-Nitrosopyrrolidin, N-Nitrosoäthylmethylamin, N-Nitroso-äthyl-n-propylamin und N-Nitroso-methyl-n-propylamin, wobei das letztgenannte Nitrosamin erstmals im Zigarettenrauch nachgewiesen wurde. Gleischzeitig wurden Korrelationen des Nitrosamingehaltes zum Gehalt des jewelligen Tabaks bzw. Kondensates an Nitrat, Gesamtstickstoff, Nicotin, flüchtigen Basen und Ammoniak untersucht, wobei sowohl der Nitratgehalt als auch der Gehalt an flüchtigen Basen Einfluß auf die Nitrosaminausbeute haben. Je nach Tabakprovenienz variiert der Gehalt der einzelnen Nitrosamine beträchtli, so daß als Kennzahl eine NNO-Bestimmung empfohlen wird.
Quantitative determination of volatile nitrosamines in cigarette smoke
Summary Volatile nitrosamines from the smoke of different cigarettes were enriched by manifold clean-up procedures. Amines obtained after acid catalyzed denitrosation were transformed to fluorescent derivates of 7-chloro-4-nitrobenzofuranzane (NBD-Cl). These NBD-amines separated on polyamid sheets were fluorimetrically determined with a chromatogram-spectrophotometer. Recovery rates of 60–80% were found for the different nitrosamines in cigarette smoke condensate. The following nitrosamines were quantitatively determined: N-nitrosodimethylamine, N-nitrosodiethylamine, N-nitrosopiperidine, N-nitrosopyrrolidine, N-nitrosoethylmethylamine, N-nitroso-ethyln-propylamine and N-nitroso-methyl-n-propylamine. The last mentioned nitrosamine was proved for the first time in cigarette smoke. At the same time correlations between the nitrosamine content of the corresponding tobacco or condensate and the content of nitrate, total nitrogen, nicotine, volatile bases and ammonia were investigated. The nitrate content as well as the content of volatile bases showed an influence on the nitrosamine yield. The content of the different nitrosamines varied cosiderably depending on tobacco origin, so that a NNO-determination is recommended as index.


Das Forschungsinstitut der Cigarettenindustrie e. V. wurde geschlossen  相似文献   
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