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排序方式: 共有196条查询结果,搜索用时 31 毫秒
31.
Darko B. Mitić Goran S. Jovanović Mile K. Stojčev Dragan S. Antić 《International Journal of Electronics》2013,100(3):362-375
Phase-synchronisers have many applications in VLSI circuit designs. They are used in CMOS RF circuits including phase (de)modulators, phase recovery circuits, multiphase synthesis, etc. In this article, a phase-synchroniser based on gm-C all-pass filter chain with sliding mode control is presented. The filter chain provides good controllable delay characteristics over the full range of phase and frequency regulation, without deterioration of input signal amplitude and waveform, while the sliding mode control enables us to achieve fast and predetermined finite locking time. IHP 0.25 µm SiGe BiCMOS technology has been used in design and verification processes. The circuit operates in the frequency range from 33 MHz up to 150 MHz. Simulation results indicate that it is possible to achieve very fast synchronisation time period, which is approximately four time intervals of the input signal during normal operation, and 20 time intervals during power-on. 相似文献
32.
Aleksandar Saljnikov Mirko Komatina Vasilije Manović Milan Gojak Darko Goričanec 《International Journal of Heat and Mass Transfer》2009,52(11-12):2871-2884
This paper deals with thermal radiation properties of ash deposits on a pulverized coal boiler of an electric power plant. Normal emittance spectra in the 2.5–25 μm interval, and total normal emittance, were measured on 4 kinds of ash layers of a mm magnitude order thickness, at 560 → 1460 → 560 K in heating and cooling. It was found that ash powder layers are opaque for infrared radiation. The emittance increases with ash radiation wavelength and temperature. Ash powder is sintered and fused above 1200 K. The emittance of the sintered layer is above that of the unsintered layer. The authors propose, and explain by an example, correlating the experimentally obtained emittance spectra of ash deposits with a continuous curve, the formula of which defines the dependence of emittance on wavelength and temperature, i.e. ε = ε(λ,Т). Use of this formula, with parameter values determined by the proposed methodology, may greatly simplify the practical application of the experimentally determined emittances in the thermal design of existing and new steam boiler furnaces. 相似文献
33.
Olivera Mitrovi Ajti Tijana Suboti
ki Milo Dikli Dragoslava iki Milica Vukoti Teodora Dragojevi Emilija
ivkovi Darko Anti Vladan oki 《International journal of molecular sciences》2022,23(13)
The calcium-binding proteins S100A4, S100A8, and S100A9 are upregulated in chronic lymphocytic leukemia (CLL), while the S100A9 promotes NF-κB activity during disease progression. The S100-protein family has been involved in several malignancies as mediators of inflammation and proliferation. The hypothesis of our study is that S100A proteins are mediators in signaling pathways associated with inflammation-induced proliferation, such as NF-κB, PI3K/AKT, and JAK/STAT. The mononuclear cells (MNCs) of CLL were treated with proinflammatory IL-6, anti-inflammatory IL-10 cytokines, inhibitors of JAK1/2, NF-κB, and PI3K signaling pathways, to evaluate S100A4, S100A8, S100A9, and S100A12 expression as well as NF-κB activation by qRT-PCR, immunocytochemistry, and immunoblotting. The quantity of S100A4, S100A8, and S100A9 positive cells (p < 0.05) and their protein expression (p < 0.01) were significantly decreased in MNCs of CLL patients compared to healthy controls. The S100A levels were generally increased in CD19+ cells compared to MNCs of CLL. The S100A4 gene expression was significantly stimulated (p < 0.05) by the inhibition of the PI3K/AKT signaling pathway in MNCs. IL-6 stimulated S100A4 and S100A8 protein expression, prevented by the NF-κB and JAK1/2 inhibitors. In contrast, IL-10 reduced S100A8, S100A9, and S100A12 protein expressions in MNCs of CLL. Moreover, IL-10 inhibited activation of NF-κB signaling (4-fold, p < 0.05). In conclusion, inflammation stimulated the S100A protein expression mediated via the proliferation-related signaling and balanced by the cytokines in CLL. 相似文献
34.
Barbara Sita Mihaela Bobi-Rasonja Goran Mrak Sara Trnski Magdalena Krbot Skori Darko Orekovi Vinka Knezovi
eljka Petelin Gade Zdravko Petanjek Goran imi Danijela Kolenc Nataa Jovanov Miloevi 《International journal of molecular sciences》2022,23(15)
The extracellular matrix (ECM) is an important regulator of excitability and synaptic plasticity, especially in its highly condensed form, the perineuronal nets (PNN). In patients with drug-resistant mesial temporal lobe epilepsy (MTLE), hippocampal sclerosis type 1 (HS1) is the most common histopathological finding. This study aimed to evaluate the ECM profile of HS1 in surgically treated drug-resistant patients with MTLE in correlation to clinical findings. Hippocampal sections were immunohistochemically stained for aggrecan, neurocan, versican, chondroitin-sulfate (CS56), fibronectin, Wisteria floribunda agglutinin (WFA), a nuclear neuronal marker (NeuN), parvalbumin (PV), and glial-fibrillary-acidic-protein (GFAP). In HS1, besides the reduced number of neurons and astrogliosis, we found a significantly changed expression pattern of versican, neurocan, aggrecan, WFA-specific glycosylation, and a reduced number of PNNs. Patients with a lower number of epileptic episodes had a less intense diffuse WFA staining in Cornu Ammonis (CA) fields. Our findings suggest that PNN reduction, changed ECM protein, and glycosylation expression pattern in HS1 might be involved in the pathogenesis and persistence of drug-resistant MTLE by contributing to the increase of CA pyramidal neurons’ excitability. This research corroborates the validity of ECM molecules and their modulators as a potential target for the development of new therapeutic approaches to drug-resistant epilepsy. 相似文献
35.
This article addresses a formal model of a distributed computation multi-agent system. This model has evolved from the experimental research on using multi-agent systems as a ground for developing fuzzy cognitive maps. The main paper contribution is a distributed computation multi-agent system definition and mathematical formalization based on automata theory. This mathematical formalization is tested by developing distributed computation multi-agent systems for fuzzy cognitive maps and artificial neural networks – two typical distributed computation systems. Fuzzy cognitive maps are distributed computation systems used for qualitative modeling and behavior simulation, while artificial neural networks are used for modeling and simulating complex systems by creating a non-linear statistical data model. An artificial neural network encapsulates in its structure data patterns that are hidden in the data used to create the network. Both of these systems are well suited for formal model testing. We have used evolutionary incremental development as an agent design method which has shown to be a good approach to develop multi-agent systems according to the formal model of a distributed computation multi-agent system. 相似文献
36.
Hybrid chloroperoxidase‐magnetic nanoparticle clusters: effect of functionalization on biocatalyst performance 下载免费PDF全文
37.
There is a lack of information in the United Kingdom on the prevalence of third molars in older patients. The aim of this study was therefore to define the pattern of lower third molar retention in UK dental practice attenders aged 35 years and over. A random sample of 599 eligible patients from a rural dental practice were included in the study. Information was obtained from clinical notes and panoramic radiographs. Data collected included age, gender, presence or absence of lower third molars, number of teeth present in the lower arch and eruption status. Two hundred and sixty-four (44.1 per cent) had at least one lower third molar present (mean age = 57.1 years) while 335 (55.9 per cent) had no lower third molars (mean age = 50.2 years). The data suggest that a greater proportion of men than women retain at least one lower third molar although this finding was not statistically significant. Seventy per cent of retained lower third molars reported in the study were fully erupted. Sixty per cent were vertically placed. There was an association between age and number of teeth present (chi 2 = 38.85, 4DF, P < 0.05), older patients having fewer lower teeth. These data suggest that a large number of patients can expect to keep their lower third molars beyond the age of 35 years and that in many cases a conservative "wait and see' policy for lower third molars in the early twenties is appropriate. 相似文献
38.
The well-known Maclaurin symmetric mean (MSM) and the dual MSM (DMSM) are introduced as important operators to handle multiattribute group decision making (MAGDM) information. The MSM and the DMSM operators have the prominent characteristic of accurately describing the interdependence of multi-input arguments. Due to their advantage, we extend the MSM and the DMSM into the dual hesitant fuzzy environment to aggregate uncertain information. Particularly, we propose some novel aggregation operators, namely dual hesitant fuzzy MSM, weighted dual hesitant fuzzy MSM, dual hesitant fuzzy dual MSM, and weighted dual hesitant fuzzy dual MSM operators. Moreover, we study some properties and special remarks regarding different values of the parameter. With an extension of the complex proportional assessment method, we formulate a new approach for the dual hesitant fuzzy MAGDM. Finally, we test the applicability and feasibility of our proposed method by solving a mobile payment platform selection problem in Ghana. 相似文献
39.
The wind potential in western Nevada was assessed by using wind, temperature, and pressure data over a period of four and half years from four 50 m tall towers. The seasonal wind patterns for all towers show a maximum during the spring season. Diurnal wind speed patterns for all seasons and months showed a minimum during the late morning and a maximum during the late afternoon. The highest values are during the spring season with multi-annual hourly wind speeds at or above 8 m/s and relative frequency of the wind speed in the optimum turbine range (5–25 m/s) of 70% or higher for the Tonopah tower, with lower values for the other three towers. The monthly power law index values are lower than the standard value 0.147 (in general 0.13 or lower). The hourly turbulence intensities were higher at lower elevations, with values of about 0.35 or higher at the 10 m level and at lower wind speed range (5.0 m/s or less). Higher turbulence intensities were found for all towers and heights during the spring and summer seasons and lower values during the rest of the year. The daily gust factor for the 2003–2007 composite data sets shows low probabilities (2% or less) of the wind gusts exceeding 25 m/s. 相似文献
40.
Meagan Hennessy Nagaraju Indugu Bonnie Vecchiarelli Laurel Redding Joseph Bender Christa Pappalardo Miranda Leibstein John Toth Darko Stefanovski Ananya Katepalli Satvik Garapati Dipti Pitta 《Journal of dairy science》2021,104(6):7225-7232
Diarrhea is a major cause of illness and death in preweaned calves and causes significant economic losses to producers. A better understanding of the fecal microbiota in diarrheic and nondiarrheic calves could lead to improved treatment and prevention strategies. The purpose of this study was to compare the fecal microbiota of diarrheic and nondiarrheic calves to improve our understanding of what constitutes a healthy fecal microbiota in preweaned calves. At each of 7 farms, fecal samples were obtained from 1 to 3 diarrheic Holstein dairy calves (2 to 17 d old at sampling time) and age-matched (within 5 d) nondiarrheic controls for a total of 20 samples. Calves were fed either acidified bulk milk, pasteurized or unpasteurized waste milk, or milk replacer depending on farm. Fecal samples were extracted for genomic DNA, PCR-amplified for the V1–V2 region of the 16S rRNA bacterial gene, sequenced on the Illumina MiSeq (Illumina Inc., San Diego, CA) platform, and analyzed using QIIME2. Firmicutes and Bacteroidetes were the most abundant phyla in both groups; Fusobacteria was numerically more abundant in the diarrheic group, whereas Proteobacteria and Actinobacteria were numerically more abundant in the nondiarrheic group. At the genus level, Bacteroides was the most abundant genus in both groups and was numerically more abundant in the nondiarrheic group. Results from the mixed-effects regression model showed that Faecalibacterium and Butyricimonas were more abundant in the nondiarrheic calves, whereas Clostridium and Peptostreptococcus were more abundant in the diarrheic calves. Our results indicate that commensal bacteria acquired in the neonatal period may have been replaced with potential pathogens in diarrheic calves, which may have contributed to the incidence of diarrhea either directly or indirectly. 相似文献