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41.
Yuri Ermoliev Tatiana Ermolieva Guenther Fischer Marek Makowski 《Annals of Operations Research》2010,177(1):9-19
The paper analyzes the implications of extreme events on the proper choice of discounting. Any discounting with constant or
declining rates can be linked to random “stopping time” events, which define the internal discount-related horizons of evaluations.
Conversely, any stopping time induces a discounting, in particular, with the standard discount rates. The expected duration
of the stopping time horizon for discount rates obtained from capital markets does not exceed a few decades and, as such,
these rates may significantly underestimate the net benefits of long-term decisions. The alternative undiscounted stopping
time criterion allows to induce social discounting focusing on arrival times of potential extreme events rather then horizons
of market interests. Induced discount rates are conditional on the degree of social commitment to mitigate risk. In general,
extreme events affect these rates, which alter the optimal mitigation efforts that, in turn, change events. The use of undiscounted
stopping time criteria requires stochastic optimisation methods. 相似文献
42.
Guenther Fuellerer Karl F. Doerner Richard F. Hartl Manuel Iori 《European Journal of Operational Research》2010
This paper addresses an important combination of three-dimensional loading and vehicle routing, known as the Three-Dimensional Loading Capacitated Vehicle Routing Problem. The problem calls for the combined optimization of the loading of freight into vehicles and the routing of vehicles along a road network, with the aim of serving customers with minimum traveling cost. Despite its clear practical relevance in freight distribution, the literature on this problem is very limited. This is because of its high combinatorial complexity. 相似文献
43.
Bob D. Guenther Paul W. Kruse 《International Journal of Infrared and Millimeter Waves》1986,7(8):1091-1109
A brief report on the results of a workshop concerning submillimeter wave detection held September 34, 1985. 相似文献
44.
Philip W. Kletnieks Ann J. Liang Raluca Craciun Justin O. Ehresmann Dr. David M. Marcus Dr. Vinesh A. Bhirud Dr. Meghan M. Klaric Miranda J. Hayman Darryl R. Guenther Olesya P. Bagatchenko David A. Dixon Prof. Bruce C. Gates Prof. James F. Haw Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2007,13(26):7267-7267
45.
The thermal decomposition of polytetrafluoroethylene (TFE, Teflon), high and low density polyethylene (HDP and LDP), Delrin Acetal (DA), AVCO Phenolic Fiberglass (APFG), and carbon phenolic (CP), were studied by a thermogravimetric technique which utilized a constant heating rate. Loss in sample weight was recorded as a function of time or temperature from room temperature to approximately 700°. Reaction orders were established from logarithmic rate versus temperature plots. Arrhenius frequency factors and overall activation energies were determined from computerized integrations of the appropriate rate equations in which the results were treated on the basis of first-order reaction mechanisms for specific temperature regions. Zero-order mechanisms were estimated by the usual graphical methods.
The authors wish to acknowledge the many hours of valued assistance accomplished by Leonie Boehmer who performed all computational calculations reported herein and for the programming and compilation of data for the CDC 6061 computer. Acknowledgment is also extended to Mark Middleton who assisted with the technical measurements and calculations presented in this report. 相似文献
Zusammenfassung Die thermische Zersetzung von Polytetrafluoräthylen (TFE, Teflon), von Polyäthylen niedriger und hoher Dichte (HDP und LDP), von Delrin Acetal (DA), von AVCO Phenolglaswolle (APFG) und von Phenolkohle (CP) wurde thermogravimetrisch mit konstanter Aufheizgeschwindigkeit untersucht. Der Gewichtsverlust wurde als Funktion der Zeit und der Temperatur von Zimmertemperatur bis zu 700° registriert. Aus der Darstellung der Logarithmen der Reaktionsgeschwindigkeit gegen die Temperatur wurde die Reaktionsordnung ermittelt. Die Arrheniusschen Frequenzfaktoren und die Werte der durchschnittlichen Aktivierungsenergien wurden durch komputerierte Integrierung der geeigneten Geschwindigkeitsgleichungen bestimmt. In den entsprechenden Geschwindigkeitsgleichungen wurden für spezielle Temperaturgebiete die Ergebnisse aufgrund des Reaktionsmechanismus von erster Ordnung behandelt. Reaktionen nullter Ordnung wurden nach den üblichen graphischen Methoden ausgewertet.
Résumé Etude de la décomposition thermique du polytétrafluoroéthylène (Teflon), du polyethylene haute et basse densité, de l'acétal Delrin, de la fibre de verre phénolique AVCO et du carbone phénolique par TG à vitesse d'échauffement constante. Enregistrement de la perte de poids en fonction du temps ou de la température, depuis la température ambiante jusqu'à 700°C environ. Détermination de l'ordre des réactions en portant le logarithme de la vitesse en fonction de la température. Détermination des facteurs de fréquence et des énergies d'activation moyennes par intégration numérique des équations de vitesse appropriées en traitant les résultats sur la base de mécanismes réactionnels du 1er ordre dans les domaines de température correspondants. Emploi des méthodes graphiques habituelles dans le cas des réactions d'ordre zéro.
(, ), c ( , ), (), () () c . ( , , 700°). . . . .
The authors wish to acknowledge the many hours of valued assistance accomplished by Leonie Boehmer who performed all computational calculations reported herein and for the programming and compilation of data for the CDC 6061 computer. Acknowledgment is also extended to Mark Middleton who assisted with the technical measurements and calculations presented in this report. 相似文献
46.
47.
48.
M. Swarnalatha A. F. Stewart A. H. Guenther C. K. Carniglia 《Applied Physics A: Materials Science & Processing》1992,54(6):533-537
The optical and structural properties of films deposited from laser sintered Zirconia (ZrO2), Hafnia (HfO2), and Yttria (Y2O3) and from the commercially available (unprocessed material) Zirconia, Hafnia and Yttria, were studied and compared. All the films had low absorption. Films deposited from the laser sintered material had very low optical inhomogeneity. ZrO2 films showed negative inhomogeneity for films deposited from the unprocessed material. The refractive index increased for ZrO2 films deposited from the laser sintered material. HfO2 and Y2O3 films showed positive inhomogeneity when deposited from the unprocessed material. The refractive index of the films of these materials decreased when deposited from the laser sintered material. The thin films of ZrO2 and Y2O3 prepared from laser sintered material had stable monoclinic and cubic structures respectively while HfO2 films were found to be amorphous. 相似文献
49.
Margarita Guenther Gerald Gerlach Cathrin Corten Dirk Kuckling Martin Muller Zhangman Shi Joerg Sorber Karl-Friedrich Arndt 《Macromolecular Symposia》2007,254(1):314-321
Summary: A rapidly expanding field of on-line process monitoring and on-line control in biotechnology, food industry, pharmaceutical industry, process chemistry, environmental measuring technology, water treatment and sewage processing requires the development of new micro fabricated reliable chemical and biosensors that are specific for particular species and can attain the analytic information in a faster, simpler and cheaper manner. Using a functionalised polymer coating in sensors provides the possibility to detect, transmit and record the information regarding the concentration change or the presence of a specific analyte (a chemical or biological substance that needs to be measured) by producing a signal proportional to the concentration of the target analyte. However, the sensor response time and signal reproducibility are limited by the visco-elastical and hysteresis behaviour of the polymer material. We propose some methods improving the properties of the chemical sensors on the basis of thermo-shrinking N-isopropylacrylamide (NIPAAm) copolymer gels. 相似文献
50.
C. Paschke A. Leisner A. Hester K. Maass S. Guenther W. Bouschen B. Spengler 《Journal of the American Society for Mass Spectrometry》2013,24(8):1296-1306
Mass spectrometric imaging (MSI) techniques are of growing interest for the Life Sciences. In recent years, the development of new instruments employing ion sources that are tailored for spatial scanning allowed the acquisition of large data sets. A subsequent data processing, however, is still a bottleneck in the analytical process, as a manual data interpretation is impossible within a reasonable time frame. The transformation of mass spectrometric data into spatial distribution images of detected compounds turned out to be the most appropriate method to visualize the results of such scans, as humans are able to interpret images faster and easier than plain numbers. Image generation, thus, is a time-consuming and complex yet very efficient task. The free software package “Mirion,” presented in this paper, allows the handling and analysis of data sets acquired by mass spectrometry imaging. Mirion can be used for image processing of MSI data obtained from many different sources, as it uses the HUPO-PSI-based standard data format imzML, which is implemented in the proprietary software of most of the mass spectrometer companies. Different graphical representations of the recorded data are available. Furthermore, automatic calculation and overlay of mass spectrometric images promotes direct comparison of different analytes for data evaluation. The program also includes tools for image processing and image analysis. Figure
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