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21.
One of the possible alternatives for creating materials for the regeneration of bone tissue supporting comprehensive reconstruction is the incorporation of active substances whose controlled release will improve this process. This systematic review aimed to identify and synthesize in vitro studies that assess the suitability of polyphenolics as additives to polymer-ceramic composite bone regeneration materials. Data on experimental studies in terms of the difference in mechanical, wettability, cytocompatibility, antioxidant and anti-inflammatory properties of materials were synthesized. The obtained numerical data were compiled and analyzed in search of percentage changes of these parameters. The results of the systematic review were based on data from forty-six studies presented in nineteen articles. The addition of polyphenolic compounds to composite materials for bone regeneration improved the cytocompatibility and increased the activity of early markers of osteoblast differentiation, indicating a high osteoinductive potential of the materials. Polyphenolic compounds incorporated into the materials presumably give them high antioxidant properties and reduce the production of reactive oxygen species in macrophage cells, implying anti-inflammatory activity. The evidence was limited by the number of missing data and the heterogeneity of the data.  相似文献   
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Alzheimer’s disease (AD) is a progressive condition and the most common cause of dementia worldwide. The neuropathological changes characteristic of the disorder can be successfully detected before the development of full-blown AD. Early diagnosis of the disease constitutes a formidable challenge for clinicians. CSF biomarkers are the in vivo evidence of neuropathological changes developing in the brain of dementia patients. Therefore, measurement of their concentrations allows for improved accuracy of clinical diagnosis. Moreover, AD biomarkers may provide an indication of disease stage. Importantly, the CSF biomarkers of AD play a pivotal role in the new diagnostic criteria for the disease, and in the recent biological definition of AD by the National Institute on Aging, NIH and Alzheimer’s Association. Due to the necessity of collecting CSF by lumbar puncture, the procedure seems to be an important issue not only from a medical, but also a legal, viewpoint. Furthermore, recent technological advances may contribute to the automation of AD biomarkers measurement and may result in the establishment of unified cut-off values and reference limits. Moreover, a group of international experts in the field of AD biomarkers have developed a consensus and guidelines on the interpretation of CSF biomarkers in the context of AD diagnosis. Thus, technological advancement and expert recommendations may contribute to a more widespread use of these diagnostic tests in clinical practice to support a diagnosis of mild cognitive impairment (MCI) or dementia due to AD. This review article presents up-to-date data regarding the usefulness of CSF biomarkers in routine clinical practice and in biomarkers research.  相似文献   
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Background: Severe outcomes of COVID-19 account for up to 15% of all cases. The study aims to check if any gene variants related to cardiovascular (CVD) and pulmonary diseases (PD) are correlated with a severe outcome of COVID-19 in a Polish cohort of COVID-19 patients. Methods: In this study, a subset of 747 samples from unrelated individuals collected across Poland in 2020 and 2021 was used and whole-genome sequencing was performed. Results: The GWAS analysis of SNPs and short indels located in genes related to CVD identified one variant significant in COVID-19 severe outcome in the HADHA gene, while for the PD gene panel, we found two significant variants in the DRC1 gene. In this study, both potentially protective and risk variants were identified, of which variants in the HADHA gene deserve the most attention. Conclusions: This is the first study reporting the association between the HADHA and DRC1 genetic variants and COVID-19 severe outcome based on the cohort WGS analysis. Although all the identified variants are localised in introns, they may be correlated and therefore inherited along with other risk variants, potentially causative to severe outcome of COVID-19 but not discovered yet.  相似文献   
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Levels of 13 pesticides in 40 honey samples form Poland are reported. A rapid and sensitive method was developed for the LC-ESI-MS/MS determination of multi-class pesticide residues in honey samples. Liquid–liquid extraction (LLE) on a diatomaceous earth support (requiring the use of small amounts of organic solvent), followed by chromatographic separation on a C18 column and gradient elution were employed. The method quantifies over a dynamic linear range from respective MQLs (0.06–1.3 ng/g) to 5 ng/g. Matrix effects were evaluated by comparing the slopes of matrix-matched and solvent-based calibration curves. The mean recoveries obtained for three fortification levels (0.5, 1.0 and 4.0 ng/g) were 63–117% for most compounds, with an expanded uncertainty of <10%. The results for real honey samples collected from five regions of Poland (Pomerania, Wielkopolska, Lublin Region, Lower and Upper Silesia), showed that residue concentrations were <5 ng/g and did not pose a threat to human health.  相似文献   
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With the modern tools of metrology we can measure almost all variables in the phenomenon field of a working machine, and some of measuring quantities can be symptoms of machine condition. On this basis we can form the symptom observation matrix for condition monitoring. From the other side we know that contemporary complex machines can have many modes of failure/damage, so called faults. The paper presents the method of extraction of fault information from the symptom observation matrix by means of singular value decomposition, in the form of generalized fault symptoms. However, at the beginning of monitoring we do not know the sensitivity of potential symptoms to the given machine faults and to its overall condition. Hence, some method of symptom observation matrix optimization leading to redundancy minimization is presented first time in this paper. This gives the possibility to assess the diagnostic contribution of every primary measured symptom. Also in the paper some possibility to assess symptom limit value, based on symptom reliability is considered. These concepts are illustrated by symptom observation matrix processing with the special program and the data are taken directly from the machine vibration condition monitoring area.  相似文献   
28.
Carbon nanotubes were used to modify a polyacrylonitrile (PAN) polymer solution before the manufacture of the carbon fiber precursor. The modified PAN fibers were spun from a dimethylformamide solution containing a small amount of single-walled carbon nanotubes. The fibers were characterized by thermogravimetry and optical and scanning electron microscopy. Structure, morphology, and selected properties of the composite polymeric fibers and the fibers after carbonization are characterized. The mechanical properties of the fibers are examined. It is found that nanotubes in the PAN solution have a strong tendency to form agglomerates that inhibit suitable macromolecular chain orientation of the carbon fiber precursor. Fibers manufactured from such a solution have similar mechanical properties to those from a pure PAN precursor, and after carbonization the resultant carbon fibers are very weak. A comparison of pure carbon fibers and those containing nanotubes reveals slight differences in their structural ordering.  相似文献   
29.
This article presents application of polymer inclusion membranes (PIM) containing polymer matrices: cellulose triacetate (CTA) or poly(vinyl) chloride (PVC), o‐nitrophenyloctyl ether (NPOE) as a plasticizer and phosphonium ionic liquids, i.e., trihexyltetradecylphosphonium chloride (Cyphos IL 101), bis(2,4,4‐trimethylpentyl)phosphinate (Cyphos IL 104) and tributyltetradecylphosphonium chloride (Cyphos IL 167), as carriers for Zn(II) transport from chloride medium. Cyphos IL167 application as an ion carrier in PIMs is reported for the first time. The membrane composition is found to affect Zn(II) transport significantly. SEM and AFM images show the differences in the surface morphology of PVC and CTA based membranes. Better transport abilities of CTA membranes (Zn(II) recovery factors exceed 80%) compared with those of PVC, indicate that the structural differences between the two polymers play a crucial role for the membrane permeability. The best initial flux and permeability coefficient are obtained for the membranes with Cyphos IL 101 and Cyphos IL 104 as carriers. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42319.  相似文献   
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