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101.
Jurgen Pfeffer 《中国通信》2013,10(3):82-90
The human brain is built to process complex visual impressions within milliseconds. In comparison with sequentially coded spoken language and written texts, we are capable of consuming graphical information at a high bandwidth in a parallel fashion, producing a picture worth more than a thousand words. Effective information visualization can be a powerful tool to capture people’s attention and quickly communicate large amounts of data and complex information. This is par-ticularly important in the context of commu-nication data, which often describes entities (people, organizations) and their connections through communication. Visual analytics ap-proaches can optimize the user-computer in-teraction to gain insights into communication networks and learn about their structures. Network visualization is a perfect instrument to better communicate the results of analysis. The precondition for effective information visualization and successful visual reasoning is the capability to draw “good” pictures. Even though communication networks are often large, including thousands or even millions of people, underlying visualization principles are identical to those used for visualizing smaller networks. In this article, you will learn about these principles, giving you the ability to as-sess the quality of network visualizations and to draw better network pictures by yourself. 相似文献
102.
This paper adds to the growing empirical evidence on the relationship between patenting and publishing among university employees.
Data from all Norwegian universities and a broad set of disciplines is used, consisting of confirmed patent inventors and
group of peers without patents matched to the inventors by controlling for gender, age, affiliation and position. In general,
the findings support earlier investigations concluding that there is a positive relationship between patenting and publishing.
There are, however, important differences among fields, universities and possibly types of academic entrepreneurs, underscoring
the need to look at nuanced and contextual factors when investigating the effects of patenting. 相似文献
103.
Effect of solvent strength and operating pressure on the formation of submicrometer polymer particles in supercritical microjets 总被引:1,自引:0,他引:1
Abhijit Gokhale Boris Khusid Rajesh N. Dave Robert Pfeffer 《The Journal of Supercritical Fluids》2007,43(2):341
A supercritical antisolvent (SAS) process is described which utilizes a mixture of thermodynamically good and poor polymer solvents and micronozzles. Experiments were conducted on polyvinylpyrrolidone (PVP) solutions in a mixture of dichloromethane (DCM) (a good solvent) and acetone (a poor solvent). Decreasing the nozzle diameter and the fluid velocity were shown to favor the disintegration of supercritical jets into drops. Mass transport of CO2 into, and solvents out of, the falling supercritical drops, rather than mass transport during jet breakup, are found to control the particle formation. Varying the acetone content of the solvent, the nozzle diameter and the jet velocity are demonstrated to provide an efficient method to decrease the particle diameter to several tens of nanometers and smooth their surface irregularities. The proposed method is expected to be applicable to a wide variety of polymers. 相似文献
104.
Oechsner R. Pfeffer M. Frickinger J. Schellenberger M. Roeder G. Pfitzner L. Ryssel H. Fritzsche M. Kaushik V. Renaud D. Danel A. Claeys C. Bearda T. Lering M. Graef M. Murphy B. Walther H. Hury S. 《Semiconductor Manufacturing, IEEE Transactions on》2007,20(3):215-221
This paper describes the objectives and results of a joint European project named FLYING WAFER. The goal of the project was to provide a methodology for interlinking European R&D centers in micro and nano technologies to a distributed 300-mm CMOS R&D line. The project was carried out as a feasibility study. Therefore, the results provide a model and concept which has the potential of guaranteeing a safe and fast exchange of wafers and data between European R&D nodes to allow multisite processing. An implementation phase is planned as a second step. 相似文献
105.
106.
Jose A. Quevedo Ayokunle Omosebi Robert Pfeffer 《American Institute of Chemical Engineers》2010,56(6):1456-1468
The quality of gas–solid fluidization of agglomerates of nanoparticles has been greatly enhanced by adding a secondary flow in the form of a high‐velocity jet produced by one or more micronozzles pointing vertically downward toward the distributor. The micronozzles produced a jet with sufficient velocity (hundreds of meters per second), turbulence, and shear to break‐up large nanoagglomerates, prevent channeling, curtail bubbling, and promote liquid‐like fluidization. For example, Aerosil R974, an agglomerate particulate fluidization (APF) type nanopowder, expanded up to 50 times its original bed height, and difficult to fluidize agglomerate bubbling fluidization (ABF) type nanopowders, such as Aeroxide TiO2 P25, were converted to APF type behavior, showing large bed expansions and homogeneous fluidization without bubbles. Microjet‐assisted nanofluidization was also found to improve solids motion and prevent powder packing in an internal, is easily scaled‐up, and can mix and blend different species of nanoparticles on the nanoscale. © 2009 American Institute of Chemical Engineers AIChE J, 2010 相似文献
107.
The Mitochondrial Amidoxime Reducing Component (mARC): Involvement in Metabolic Reduction of N‐Oxides,Oximes and N‐Hydroxyamidinohydrazones
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Heyka H. Jakobs Dr. Danilo Froriep Dr. Antje Havemeyer Prof. Ralf R. Mendel Dr. Florian Bittner Prof. Bernd Clement 《ChemMedChem》2014,9(10):2381-2387
The mitochondrial amidoxime reducing component (mARC) is a molybdenum‐containing enzyme and capable of reducing N‐hydroxylated structures such as amidoxime prodrugs. In this study, we tested the involvement of mARC in the reduction of N‐oxides (amitriptyline‐N‐oxide, nicotinamide‐N‐oxide), oximes ((E)‐/(Z)‐2,4,6‐trimethylacetophenonoxime) and a N‐hydroxyamidinohydrazone (guanoxabenz). All groups are reduced by mARC proteins, and the enzymes are therefore involved in the interconversion of N‐oxygenated metabolites originating from cytochrome P450s and flavin‐containing monooxygenases. In addition, these structures open up further options for serving as prodrugs. Thus, with respect to these reactions, testing of candidates with N‐oxygenated structures should not solely be carried out in microsomal enzyme sources but as well in mitochondria. However, differences in the reduction of oximes and N‐oxides between the two isoforms, namely mARC1 and mARC2, were detectable; N‐oxides are exclusively reduced by mARC1. We therefore assume differences between the so far unknown 3D structures of the two proteins. 相似文献
108.
Jonathan R.I. Lee Rachel L. O’Malley Antje Vollmer Trevor Rayment 《Electrochimica acta》2010,55(28):8532-8538
Zn K-edge X-ray absorption spectroscopy (XAS) has been used to investigate the structure of Zn monolayers prepared on Au(1 1 1) electrodes via underpotential deposition (UPD) from phosphate supporting electrolyte. Theoretical modeling of the XAS data indicates that the Zn adatoms adopt a commensurate (√3 × √3)R30° (θsc = 0.33) adlayer structure and reside within the 3-fold hollow sites of the Au(1 1 1) surface. Meanwhile, phosphate counter-ions co-adsorb on the UPD adlayer and bridge between the Zn adatoms in a (√3 × √3)R30° (θsc = 0.33) configuration, with each phosphorous atom residing above a vacant 3-fold hollow site of the Au(1 1 1). Significantly, this surface structure is invariant between the electrochemical potential for UPD adlayer formation and the onset of bulk Zn electrodeposition. Analysis of the Zn K-edge absorption onset also presents the possibility that the Zn adatoms do not fully discharge during the process of UPD, which had been proposed in prior voltammetric studies of the phosphate/Zn(UPD)/Au(1 1 1) system. 相似文献
109.
110.
PE Ure?a GA Lamas G Mitchell GC Flaker SC Smith FJ Wackers P McEwan MA Pfeffer 《Canadian Metallurgical Quarterly》1999,33(1):180-185
OBJECTIVES: We assessed the abilities of two methods to measure ejection fraction (EF)-radionuclide ventriculography (RVG) and contrast left ventriculography (Cath-EFa) to predict cardiovascular events. BACKGROUND: Both RVG and Cath-EFa are commonly used methods to measure left ventricular performance and assess prognosis. Their comparative abilities to predict clinical events have not been reported. METHODS: Both RVG EF and Cath-EFa were measured within 16 days of myocardial infarction (MI) in 688 patients. The results were divided into terciles. Prognosis by terciles was assessed for each technique. A multivariate analysis was performed to determine which EF measurement was a better predictor of prognosis. RESULTS: Average RVG-EF was 32%+/-7, while Cath-EFa was 42%+/-10. Both RVG and Cath-EFa were poorly correlated (R=0.42). Event rate declined across terciles with increasing EF for both techniques (events in lowest to highest tercile of Cath-EFa 40.7%, 25.9%, 11.6%, p < 0.001; and RVG-EF 39.9%, 26.1%, 15.6%, p < 0.001). There was concordance of terciles in 303 of 688 patients (44%). When patients in the highest RVG terciles were in the highest Cath-EFa tercile, the event rate was 7%. However, when patients in the highest RVG terciles were in the lowest Cath-EFa tercile, the event rate was 19%. Both Cath-EFa (p < 0.001) and RVG-EF (p < 0.001) were independent predictors of cardiovascular events. CONCLUSIONS: Ejection fraction measured by RVG or during catheterization is a valuable tool in the risk stratification of postinfarct patients. When disagreement is present between clinical impression and measurement by either method, the use of an alternative measurement is warranted and complementary. 相似文献