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81.
The aim was to classify lifting activities into low and high risk categories (according to The Danish Working Environment Authority guidelines) based on surface electromyography (sEMG) and trunk inclination (tri-axial accelerometer) measurements. Lifting tasks with different weights, horizontal distance and technique were performed. The lifting tasks were characterised by a feature vector composed of either the 90th, 95th or 99th percentile of sEMG activity level and trunk inclinations during the task. Linear Discriminant Analysis and a subject-specific threshold scheme were applied and lifting tasks were classified with an accuracy of 65.1–65.5%. When lifts were classified based on the subject-specific threshold scheme from low and upper back accelerometers, the accuracy reached 52.1–58.1% and 72.7–78.1%, respectively. In conclusion, the use of subject-specific thresholds from sEMG from upper trapezius and erector spinae as well as inclination of the upper trunk enabled us to identify low and high risk lifts with an acceptable accuracy.

Practitioner Summary: This study contributes to the development of a method enabling the automatic detection of high risk lifting tasks, i.e. exposure to high biomechanical loads, based on individual sEMG and kinematics from an entire working day. These methods may be more cost-effective and may complement observations commonly used by practitioners.  相似文献   

82.
The molecular and cellular mechanisms underlying the multistage processes of cancer progression and metastasis are complex and strictly depend on the interplay between tumor cells and surrounding tissues. Identification of protein aberrations in cancer pathophysiology requires a physiologically relevant experimental model. The mouse offers such a model to identify protein changes associated with tumor initiation and progression, metastasis development, tumor/microenvironment interplay, and treatment responses. Furthermore, the mouse model offers the ability to collect samples at any stage in tumor development from highly matched disease cases and controls with identical environmental and genetic backgrounds, thus providing an excellent method for biomarker discovery. Xenograft and genetically engineered mouse models have been widely used to identify proteomic patterns in tumor tissues and plasma samples associated with different stages of human cancer, including early cancer detection and development of metastasis. Here, we review proteomic strategies to identify proteins involved in key cancer processes within such animal models as well as biomarkers for diagnosis, prognosis, and monitoring of cancer progression and treatment response. Central to such studies is the ability to ensure at an early stage that the identified proteins are of clinical relevance by examining relevant specimens from larger cohorts of cancer patients.  相似文献   
83.
Fatty acid hydratases (FAHs) catalyze regio- and stereo-selective hydration of unsaturated fatty acids to produce hydroxy fatty acids. Fatty acid hydratase-1 (FA-HY1) from Lactobacillus Acidophilus is the most promiscuous and regiodiverse FAH identified so far. Here, we engineered binding site residues of FA-HY1 (S393, S395, S218 and P380) by semi-rational protein engineering to alter regioselectivity. Although it was not possible to obtain a completely new type of regioselectivity with our mutant libraries, a significant shift of regioselectivity was observed towards cis-5, cis-8, cis-11, cis-14, cis-17-eicosapentaenoic acid (EPA). We identified mutants (S393/S395 mutants) with excellent regioselectivity, generating a single hydroxy fatty acid product from EPA (15-OH product), which is advantageous from application perspective. This result is impressive given that wild-type FA-HY1 produces a mixture of 12-OH and 15-OH products at 63 : 37 ratio (12-OH : 15-OH). Moreover, our results indicate that native FA-HY1 is at its limit in terms of promiscuity and regiospecificity, thus it may not be possible to diversify its product portfolio with active site engineering. This behavior of FA-HY1 is unlike its orthologue, fatty acid hydratase-2 (FA-HY2; 58 % sequence identity to FA-HY1), which has been shown earlier to exhibit significant promiscuity and regioselectivity changes by a few active site mutations. Our reverse engineering from FA-HY1 to FA-HY2 further demonstrates this conclusion.  相似文献   
84.
The synthesis and characterization of a number of so-called thermo-cleavable solvents are described with their application in all-air, all-solution and all-screen-printed polymer solar cells. These solvents were developed to meet some requirements for printing techniques such as long “open time” combined with fast drying on heating that cannot be attained with the usual solvents used for conjugated polymers. The new solvents have low volatility at ambient conditions, but decompose thermally at 130-180 °C to low-boiling and highly volatile products. Characterization by thermogravimetric analysis (TGA) and high-temperature NMR established the onset temperature of decomposition, the rate of the reaction and the nature of the products. Printing experiments with inks based on these solvents together with conjugated polymers are exemplified for polymer solar cell devices to show how they enable large-scale production of polymer solar cells using screen printing. Screen-printed solar cells are still very inferior to state of the art P3HT/PCBM technology, but it is our view that it is necessary to explore these printing technologies if polymer solar cells are to ever become commercial products.  相似文献   
85.
Structural characterization of aggregates and fibrils of the Aβ protein is pivotal to the molecular-level elucidation of Alzheimer's disease (AD). AFM-IR spectroscopy provides nanoscale resolution, and thus allows the interrogation of individual aggregates and fibrils. During aggregation of Aβ, we observed mainly disordered Aβ at t=15 min, but substantial structural diversity including the co-existence of parallel and antiparallel β-sheets within a large amorphous aggregate at t=2 hours, while fibrils exhibited the expected signature of parallel β-sheets at t=1 week. The resonance observed for parallel β-sheets at t=2 hours coincides with that observed for fibrils (at 1634 cm−1), thus indicating that fibril-like species exist within the large aggregates. Therefore, nucleation might occur within such species, in analogy to current theories of protein crystallization in which nucleation occurs within large protein clusters. Cu2+ perturbs Aβ aggregation, catalysing rapid formation of amorphous aggregates with diverse secondary structure, but inhibiting fibril growth.  相似文献   
86.
Unlike ambient pressure silicate glasses, some phosphosilicate glasses contain sixfold-coordinated silicon (Si6) units even when prepared at ambient pressure. The variation in the fraction of Si6 with composition remains a topic of interest, both for technological applications of phosphosilicate glasses and for fundamental understanding of the glass structure. In this work, we use statistical mechanical modeling to predict the composition–structure relationships in Na2O–P2O5–SiO2 and CaO–P2O5–SiO2 glasses. This is achieved by accounting for the enthalpic and entropic contributions to the interactions between each pairwise modifier ion and structural unit. The initial enthalpy parameters are obtained based on experimental structural data for binary Na2O–SiO2, CaO–SiO2, Na2O–P2O5, and CaO–P2O5 glasses, which can then be transferred to predict the structure of mixed former glasses. This approach has previously been used to predict the short-range structure of borosilicate and aluminoborate glass systems. However, here we show that the formation of Si6 must be specifically included to make accurate predictions of the composition–structure relationships in phosphosilicate glasses. After incorporating the formation mechanism of Si6 in the statistical mechanics model, we find an excellent agreement between model predictions and experimental structure data for Na2O–P2O5–SiO2 and CaO–P2O5–SiO2 glasses.  相似文献   
87.
For the first time DNA coils formed by rolling circle amplification are quantified on‐chip by Brownian relaxation measurements on magnetic nanobeads using a magnetoresistive sensor. No external magnetic fields are required besides the magnetic field arising from the current through the sensor, which makes the setup very compact. Limits of detection down to 500 Bacillus globigii spores and 2 pM of Vibrio cholerae are demonstrated, which are on the same order of magnitude or lower than those achieved previously using a commercial macro‐scale AC susceptometer. The chip‐based readout is an important step towards the realization of field tests based on rolling circle amplification molecular analyses.  相似文献   
88.
冰山住宅     
冰山住宅的外形轮廓清晰、线条分明,11个白色的峰顶为奥尔胡斯天际线增添了浓墨重彩的一笔,无论从向陆面还是从临海面看去都是如此.项目地理位置优越,位于奥尔胡斯新区的黄金地段——奥尔胡斯东岸最远端的港湾区,共包含208间公寓.正如许多其他日益破败的工业港口区一样,先前的奥尔胡斯集装箱港正逐渐被改造成为一个充满活力的新社区,各种各样的居住、教育机构、办公、零售、运动和休闲功能单元一应俱全。  相似文献   
89.
Non‐destructive lateral mapping of the thickness of the photoactive layer in poly(3‐hexyl‐thiophene) : 1‐(3‐methoxy‐carbonyl)propyl‐1‐phenyl‐(6,6)C61 (P3HT : PCBM) solar cells is demonstrated. The method employs a spatially resolved (XY) recording of ultraviolet‐visible spectra in reflection geometry at normal incidence, using a dense raster defined by a circular probe spot of 800‐µm diameter. The evaluation of the thickness of the photoactive layer at each raster point employs an algorithm‐driven comparison of the measured absorption spectrum with spectral features, as compiled from the corresponding simulated spectrum. For the robustness of the applied algorithm toward noise in the recorded absorption data to be increased, a new minimum finder algorithm is described and implemented. The thickness evaluation relies on the correct assignment of extrema in the experimental absorption spectra to the corresponding extrema in the simulated absorption spectra, and a new algorithm for this is also implemented and described. For a level of confidence for the method to be established, first thickness mapping is performed for a set of reference samples consisting of P3HT : PCBM spin‐coated on indium tin oxide‐coated float glass substrates. After this, two application examples for solar cells processed either by spin coating or slot die coating of the P3HT : PCBM layer follow. The spin‐coated solar cells have glass as the substrate with the P3HT : PCBM spun at different spinning speeds. The slot die‐coated solar cells were processed on polyethylene terephthalate foil in a roll‐to‐roll experiment involving a continuously changing P3HT : PCBM concentration along the printing direction. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
90.
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