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91.
A multicentred study derived from the COLIPA in vitro UVA method was performed to assess the influence of test conditions on UVA protection factor (UVAPF) values in terms of amplitude, reproducibility between laboratories and correlation with in vivo UVA results. Eight products with a range of in vivo UVAPF from three to 29 were used. Two different types of plates, namely high‐roughness (5 μm) and low‐roughness (2 μm) plates, were used with a different application rate for each (1.3 mg cm?2 and 0.75 mg cm?2 respectively). The UVR dose applied to both plate types followed the same principle as the original test (1.2 J. cm?2 × UVAPF0). Strong, significant correlations between in vitro and in vivo UVAPF values were observed for both plate types (Pearson correlation > 0.9, P ≤ 0.01). The correlation and slope obtained with the low‐roughness plates confirmed the previous results obtained by COLIPA. Across all laboratories, higher UVAPF values were obtained on the high‐roughness plates (P < 0.01). Reproducibility of UVAPF values between laboratories was comparable between the two plate roughness values (low roughness, COV = 8%; high roughness, COV = 12%). Considering the in vitro/in vivo comparisons, a regression slope of 0.83 was observed for the low‐roughness plates, in comparison with a value of 1.05 for the high‐roughness plates. The accuracy of the method was improved, therefore, with the use of the high‐roughness plates. With a constraint to recommend the use of only one plate type in the COLIPA UVA in vitro Test, the high‐roughness plate was selected on an on‐going basis to limit variability of results and to provide better accuracy with in vivo data.  相似文献   
92.
Ruthenium(II)–arene complexes have gained significant research interest due to their possible application in cancer therapy. In this contribution two new complexes are described, namely [{RuCl(η6-p-cymene)}2(μ-Cl)(μ-1-N,N′-naphthyl)]X (X = Cl, 1; PF6, 2), which were fully characterized by IR, NMR, and elemental microanalysis. Furthermore, the structure of 2 in the solid state was determined by a single crystal X-ray crystallographic study, confirming the composition of the crystals as 2·2MeOH. The Hirshfeld surface analysis was employed for the investigation of interactions that govern the crystal structure of 2·2MeOH. The structural data for 2 out of 2·2MeOH was used for the theoretical analysis of the cationic part [{RuCl(η6-p-cymene)}2(μ-Cl)(μ-1-N,N′-naphthyl)]+ (2a) which is common to both 1 and 2. The density functional theory, at B3LYP/6-31+G(d,p) basis set for H, C, N, and Cl atoms and LanL2DZ for Ru ions, was used for the optimization of the 2a structure. The natural bond orbital and quantum theory of atoms in molecules analyses were employed to quantify the intramolecular interactions. The reproduction of experimental IR and NMR spectra proved the applicability of the chosen level of theory. The binding of 1 to bovine serum albumin was examined by spectrofluorimetry and molecular docking, with complementary results obtained. Compound 1 acted as a radical scavenger towards DPPH and HO radicals, along with high activity towards cancer prostate and colon cell lines.  相似文献   
93.
Longevity is a complex phenotype influenced by both environmental and genetic factors. The genetic contribution is estimated at about 25%. Despite extensive research efforts, only a few longevity genes have been validated across populations. Long-lived individuals (LLI) reach extreme ages with a relative low prevalence of chronic disability and major age-related diseases (ARDs). We tested whether the protection from ARDs in LLI can partly be attributed to genetic factors by calculating polygenic risk scores (PRSs) for seven common late-life diseases (Alzheimer’s disease (AD), atrial fibrillation (AF), coronary artery disease (CAD), colorectal cancer (CRC), ischemic stroke (ISS), Parkinson’s disease (PD) and type 2 diabetes (T2D)). The examined sample comprised 1351 German LLI (≥94 years, including 643 centenarians) and 4680 German younger controls. For all ARD-PRSs tested, the LLI had significantly lower scores than the younger control individuals (areas under the curve (AUCs): ISS = 0.59, p = 2.84 × 10−35; AD = 0.59, p = 3.16 × 10−25; AF = 0.57, p = 1.07 × 10−16; CAD = 0.56, p = 1.88 × 10−12; CRC = 0.52, p = 5.85 × 10−3; PD = 0.52, p = 1.91 × 10−3; T2D = 0.51, p = 2.61 × 10−3). We combined the individual ARD-PRSs into a meta-PRS (AUC = 0.64, p = 6.45 × 10−15). We also generated two genome-wide polygenic scores for longevity, one with and one without the TOMM40/APOE/APOC1 gene region (AUC (incl. TOMM40/APOE/APOC1) = 0.56, p = 1.45 × 10−5, seven variants; AUC (excl. TOMM40/APOE/APOC1) = 0.55, p = 9.85 × 10−3, 10,361 variants). Furthermore, the inclusion of nine markers from the excluded region (not in LD with each other) plus the APOE haplotype into the model raised the AUC from 0.55 to 0.61. Thus, our results highlight the importance of TOMM40/APOE/APOC1 as a longevity hub.  相似文献   
94.
In the present paper we investigate the shear creep behavior of the single crystal super alloy CMSX‐4 at temperatures between 950 and 1100 °C and shear stresses ranging from 80 to 155 MPa. A double shear creep test technique is used to study the shear creep behavior of four specific macroscopic crystallographic shear systems defined by a specific crystallographic shear plane and a specific crystallographic shear direction (systems investigated: {001}<110>, {100}<010>, {011}<01‐1>, and {111}<01‐1>). The shear creep behavior is analyzed in terms of the shape of individual creep curves and in terms of the stress and the temperature dependence of the secondary shear creep rate. Individual creep curves are generally characterized by a pronounced primary creep range where creep rates decrease by up to three orders of magnitude. A sharp creep rate minimum is not observed. The secondary creep range starts at shear stresses of the order of 0.02 and is followed by a secondary creep range which extends over shear strain ranges of the order of 0.1. No pronounced increase of shear creep rate in the later stages of creep is observed. Norton plots yield power law stress exponents ranging from 5.5 to 9.7. The temperature dependence of the secondary creep rate is of an Arrhenius type and apparent activation energies between 549 and 690 kJ/mol were found. There is a clear influence of crystallography on shear creep rates, which vary between different macroscopic crystallographic shear systems; this effect decreases with increasing temperature. The shear creep results obtained in the present study are discussed in the light of results from uniaxial testing and in the light of underlying microscopic deformation processes.  相似文献   
95.
96.
Übersicht An einem stromrichtergespeisten permanenterregten Synchronmotor hoher Leistungsdichte werden die zu erwartenden Geräusche mit dem Ziel einer Minimierung theoretisch untersucht. Neben den Unregelmäßigkeiten in den Stromzeitverläufen sind auch die Zugkräfte des Nutenstreufeldes zu berücksichtigen. Aufgrund der berechneten Schwingungsanregung und des zu erwartenden mechanischen Verhaltens des Ständers wird die günstigste Strangzahl ausgewählt. Messungen des schwingungstechnischen Verhaltens von Modellen und von einem Prototyp sollen zeigen, ob die komplizierte Ständerkonstruktion auf einen Ring zurückgeführt werden kann. Ein Vergleich mit den abschließenden experimentellen Untersuchungen ermöglicht es, die Geräuschspektren im relevanten Drehzahlbereich zu deuten und die Leistungsfähigkeit des Berechnungsverfahrens zu bewerten.
Minimizing the acoustic noise of a high performance converter-fed permanent magnet synchronous motor
Contents The generation of force waves is calculated for a battery powered permanent-field synchronous motor with high power-to-weight ratio in order to minimize the acoustic noise. The computation also includes the forces of the slot leakage flux and considers the irregularities in the current waveform. This analysis and the prospective vibrational response of the stator construction are used to determine the optimal number of phases. Measurements of the mechanical oscillatory characteristics of stator models and of a prototype stator aim to show if the complex stator design may be treated as a radially vibrating ring. Finally, comparative experimental noise investigations enable the acoustic noise spectra to be interpreted in the relevant range of speeds and allow the outlined method of calculation to be evaluated.
  相似文献   
97.
The system Cu-Co has a metastable miscibility gap in the under-cooled liquid phase which can be accessed by electromagnetic lévitation. Unsupported two-phase liquid drops display a variety of physical phenomena, including wetting, phase separation and solidification, which can be studied on this model system. This paper reports theoretical and experimental results which have been obtained within the CuCool project, funded by ESA, DLR and CNES through the MAP programme.  相似文献   
98.
99.
In this work, one- and two-step laser dispersing of Ti6Al4V surfaces by use of elemental boron (B) as well as TiB2, ZrB2, and CrB2 was carried out with CO2 and Nd:YAG lasers using an adapted apparatus to provide inert conditions. Depending on the laser system, melt pool depths between 200 μm and more than 1000 μm were achieved, and the boride precipitates allowed an increase of the surface hardness from 350 HV0.05 in the initial state to more than 600 HV0.05. The modified surface areas were characterized by means of optical microscopy, scanning electron microscopy, and EDXS. Oscillating and cavitation erosion wear tests were carried out. For reinforcement of component surfaces with complex shape, a two-step laser deposition process and a technology for predeposition of diboride layers with defined thickness is required. The applicability of vacuum plasma spraying for predeposition is discussed. The original version of this article was published as part of the ASM Proceedings, Thermal Spray 2003: Advancing the Science and Applying the Technology, International Thermal Spray Conference (Orlando, FL), May 5–8, 2003, Basil R. Marple and Christian Moreau, Ed., ASM International, 2003.  相似文献   
100.
As part of a comprehensive study of X-ray emission from planetary surfaces and in particular the planet Mercury, we have measured fluorescent radiation from a number of planetary analog rock samples using monochromatized synchrotron radiation provided by the BESSY II electron storage ring. The experiments were carried out using a purpose built X-ray fluorescence (XRF) spectrometer chamber developed by the Physikalisch-Technische Bundesanstalt, Germany's national metrology institute. The XRF instrumentation is absolutely calibrated and allows for reference-free quantitation of rock sample composition, taking into account secondary photon- and electron-induced enhancement effects. The fluorescence data, in turn, have been used to validate a planetary fluorescence simulation tool based on the GEANT4 transport code. This simulation can be used as a mission analysis tool to predict the time-dependent orbital XRF spectral distributions from planetary surfaces throughout the mapping phase.  相似文献   
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