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21.
Wind-to-hydrogen (WH) is a promising option for reducing greenhouse gas emissions in the transport sector. Therefore, the reduction potential of fossil fuels by WH was estimated taking meteorological, geographical, and technical constraints into account. The wind resource estimation is based on the application of the high-resolution (200 m × 200 m) wind speed-wind shear model (WSWS). Together with the power curves of the six most frequently installed wind turbines in 2017, WSWS was used to assess Germany's technical wind energy potential. The WH and fossil fuel reduction potentials were calculated based on proton exchange membrane electrolysis. Results from the wind resource assessment demonstrate that in addition to the currently realized wind energy (89 TWh/yr in 2017), which is directly used for electricity generation, Germany's technical onshore potential for WH is 780 TWh/yr. This amount of renewable energy available for WH could replace 80.1% of the fossil fuels currently used in the transport sector.  相似文献   
22.
Abalone meat is a delicacy worldwide, fetching high prices and a valuable source of income for the many countries farming and exporting this commodity. The quality of abalone is based on its unique sensory properties and an analytical metabolomics method for determining the compounds related to this would serve as a valuable tool for ensuring quality and consumer satisfaction. Metabolomics is a promising “omics” tool which can be applied towards this goal; however, widely applicable parameters for the evaluation of an untargeted gas chromatography mass spectrometry (GC-MS) metabolomic approach is still lacking. GC-MS is a popular and suitable metabolomics method due to its high separation power, reproducible retention times, and selective mass detection. The aim of this study was to establish a reliable untargeted GC-MS method for analyzing firstly a standard compound mixture consisting of 10 compounds representing various compound classes and secondly applying the method in an untargeted manner to abalone muscle samples. Using a standard compound mixture with a concentration range of 1 to 100 μg/mL, the limit of detection (LOD) ranged between 0.01 and 3.30 μg/mL, the limit of quantification (LOQ) resulted in values between 0.02 and 9.49 μg/mL, the accuracy determined was <1.5 μg/mL, and the precision displayed a coefficient of variance (CV) <25 %. When evaluating the method in terms of biological samples harvested, the repeatability and intermediate precision showed CV values <50 % for most compounds measured, allowing application of this method for metabolite profiling of abalone to answer important biological questions.  相似文献   
23.
A survey of 368 shopping mall patrons (mean age 37 yrs) showed that 49% listened to radio call-in psychology programs (RCPPs), although listening was usually relatively infrequent. Listeners did not differ from nonlisteners in terms of demographic variables, psychological knowledge or well-being, or previous experience with psychological services. 86% of listeners saw RCPPs as useful, although 50% also noted potential harmful effects. The most common reasons for listening were a desire for personal information, wanting to learn about psychology, the opportunity to hear about others' problems, and amusement. An additional survey of 122 RCPP callers showed that the group was predominantly female (65%) and most commonly lived alone, that a majority of Ss had previously received some psychological treatment, and that they showed poorer psychological health than Ss in the 1st survey. A postcall interview and 3-mo follow-up indicated an improvement in psychological well-being but no change in reported stress. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
24.
Zusammenfassung Es wird eine Methode zur Bestimmung von 5-Methoxypsoralen in Sonnenschutzmitteln beschrieben. Nach säulenchromatographischer Reinigung wird der Extrakt mittels zweidimensionaler Dünnschichtchromatographie untersucht. Bei positiven Befunden wird das 5-Methoxypsoralen capillar-gaschromatographisch unter Verwendung von 5--Cholestan als innerem Standard quantitativ bestimmt. Die Ergebnisse werden durch Gaschromatographie-Massenspektrometrie (GC-MS) abgesichert. Die Wiederfindungsrate beträgt bei Kosmetika vom Emulsionstyp 70% und bei Sonnenölpräparaten 90%. Die Nachweisgrenze liegt je nach Probenart, zwischen 0,1 und 0,5 mg/kg.Mit dieser Methode wurden in 6 von 21 untersuchten Sonnenschutzmitteln bis zu 28 mg 5-Methoxypsoralen/kg nachgewiesen.
Determination of 5-methoxypsoralene in suntan-cosmetics
Summary A method for the determination of 5-methoxypsoralene in suntan-cosmetics is described. After liquid chromatographic clean-up, the final extract is screened by twodimensional thin layer chromatography. For positive extracts 5-methoxypsoralene is analysed quantitatively by capillary gas chromatography, using 5--cholestane as an internal standard and flame ionization detection (FID). The results were confirmed by gas chromatography-mass spectrometry (GC-MS). The recoveries for suntan-cosmetics of emulsion type were 70% and for tanning oils 90%. Detection limits of the method were 0,1 to 0,5 mg/kg, depending on the sample type.By application of this method 5-methoxypsoralene was detected in 6 of the 21 cosmetic products at levels up to 28 mg/kg.
  相似文献   
25.
The relaxor material Na1/2Bi1/2TiO3 (NBT) is an important basis for the development of lead‐free piezoceramics, but still many features of this material are not well understood. Here, we study the kinetics of phase transformations by octahedral tilts and A‐cation displacements in NBT by means of density functional theory calculations, employing ab initio molecular dynamics and nudged elastic band calculations. Our results show that the energetic differences between the low temperature rhombohedral, intermediate orthorhombic and other metastable phases are close to the room temperature thermal energy. Therefore, it is likely that above room temperature, several octahedral tilt patterns are present simultaneously on the local scale, just because of thermal vibration of the oxygen ions. Octahedral tilt transformations and A‐cation displacements show similarly high energy barriers, however, since the vibrational frequency of oxygen is higher, tilt transformations occur more frequently. Further, tilt transformations in which the oxygen octahedra get deformed the least are more probable to occur. We also find that the chemical A‐cation order affects energy barriers, influences the coupling between rotational and displacive modes and determines the stability of certain octahedral tilt orders. We conclude that the so‐called polar nanoregions in this material result from local octahedral tilt transformations and subsequent A‐cation displacements, which are driven by thermal vibration and are mediated by the underlying chemical order.  相似文献   
26.
A preconcentrating surface‐enhanced Raman scattering (SERS) sensor for the analysis of liquid‐soaked tissue, tiny liquid droplets and thin liquid films without the necessity to collect the analyte is reported. The SERS sensor is based on a block‐copolymer membrane containing a spongy‐continuous pore system. The sensor's upper side is an array of porous nanorods having tips functionalized with Au nanoparticles. Capillarity in combination with directional evaporation drives the analyte solution in contact with the flat yet nanoporous underside of the SERS sensor through the continuous nanopore system toward the nanorod tips where non‐volatile components of the analyte solution precipitate at the Au nanoparticles. The nanorod architecture increases the sensor surface in the detection volume and facilitates analyte preconcentration driven by directional solvent evaporation. The model analyte 5,5′‐dithiobis(2‐nitrobenzoic acid) can be detected in a 1 × 10?3m solution ≈300 ms after the sensor is brought into contact with the solution. Moreover, a sensitivity of 0.1 ppm for the detection of the dissolved model analyte is achieved.  相似文献   
27.

Background  

Red wine (RW) is rich in antioxidant polyphenols that might protect from oxidative stress related diseases, such as cardiovascular disease and cancer. Antioxidant effects after single ingestion of RW or dealcoholized RW (DRW) have been observed in several studies, but results after regular consumption are contradictory. Thus, we examined if single or repeated consumption of moderate amounts of RW or DRW exert antioxidant activity in vivo.  相似文献   
28.
A new mineral–polymer composite (FCC-PCL) performance was assessed to produce complex geometries to aid in development of controlled release tablet formulations. The mechanical characteristics of a developed material such as compactibility, compressibility and elastoplastic deformation were measured. The results and comparative analysis versus other common excipients suggest efficient formation of a complex, stable and impermeable geometries for constrained drug release modifications under compression. The performance of the proposed composite material has been tested by compacting it into a geometrically altered tablet (Tablet-In-Cup, TIC) and the drug release was compared to commercially available product. The TIC device exhibited a uniform surface, showed high physical stability, and showed absence of friability. FCC-PCL composite had good binding properties and good compactibility. It was possible to reveal an enhanced plasticity characteristic of a new material which was not present in the individual components. The presented FCC-PCL composite mixture has the potential to become a successful tool to formulate controlled-release dosage solid forms.  相似文献   
29.
This article focuses on social situations in which people are surprised about what is happening and inhibited about how to respond to the situation at hand. We study these situations by examining a classic topic in social psychology: how people respond to receiving better outcomes than are deserved. In these situations, the actions of an authority or a coworker push in the direction of accepting and enjoying the unfair outcome, whereas personal values for most people push in the direction of rejecting or being displeased with the outcome. This conflict may inhibit people's response to the advantageous but unfair outcomes. If people are indeed inhibited about how to respond to these kinds of outcomes, then lowering behavioral inhibition by reminding people of having acted in the past without inhibitions (in a manner that is unrelated to the outcomes participants subsequently receive) should affect reactions to the outcomes. Specifically, we hypothesize that because many people are prosocial and want to adhere to principles of fairness, reminders of behavioral disinhibition will lead to less pleasure with the unfairly obtained outcomes. The results of 8 experiments (conducted both inside and outside the psychology laboratory) revealed evidence for this benign disinhibition effect on various reactions to outcomes that are better than deserved. In further accordance with our line of reasoning, the effect is particularly pronounced among those who adhere to a prosocial orientation or who have adopted a prosocial mindset and is not observed among those with proself orientations or mindsets. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
30.
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