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81.
Silvia Fustinoni Federica Rossella Laura Campo Rosa Mercadante Pier Alberto Bertazzi 《The Science of the total environment》2010,408(14):2840-385
The aim of this work was to evaluate urinary benzene, toluene, ethylbenzene, m+p-xylene, o-xylene (BTEX), methyl tert-butyl ether (MTBE), ethyl tert-butyl ether (ETBE), and naphthalene (NAP) as biomarkers of exposure to environmental pollutants. Personal air and urine samples from 108 subjects belonging to the Italian general population were compared. Urinary profiles were obtained by headspace gas chromatography-mass spectrometry. BTEX, MTBE, ETBE and NAP median airborne exposures during a 5-h sampling were 4.0, 25.3, 3.8, 9.3, 3.4, 3.4, < 0.8, and 3.4 µg/m3, respectively. Meanwhile, median urinary levels, as geometric means of three determinations were: 122, 397, 74, 127, 43, 49, < 15, and 46 ng/L, respectively. Urinary benzene and toluene concentrations were 4.6- and 1.2-fold higher in smokers than in non-smokers. For most chemicals, significant positive correlations between airborne exposure (log-transformed) and the corresponding biological marker (log-transformed) were found, with Pearson's r values for correlation, ranging from 0.228 to 0.396. Multiple linear regression analysis showed that the urinary level of these chemicals was influenced by personal airborne exposure, urinary creatinine, and urinary cotinine, with R2 0.733 for benzene. Urinary chemicals are useful biomarkers of environmental exposure. Given the ease of rapidly obtaining urine samples, they represent a non-invasive alternative to blood chemical analysis. The possibility of obtaining urinary exposure profiles makes this method an appealing tool for environmental epidemiology. 相似文献
82.
Nicola Lisi Rossella Giorgi Theodoros Dikonimos Elena Salernitano Serena Gagliardi Leonardo Giorgi Vittoria Contini Piero Morales 《Diamond and Related Materials》2010,19(11):1382-1386
A novel approach to the deposition of polycrystalline diamond is presented. The technique is based on the hot filament chemical vapour deposition technique (HFCVD). While it is similar to a high plasma power “bias enhanced growth” HFCVD, it relies on a graphite filament rather than on a metal one. It was found that with an appropriate choice of the growth parameters, 4–9% CH4 in H2, filament temperature > 2200 °C, 25 mBar gas pressure, plasma power > 500 W, a long filament lifetime can be achieved, when a simultaneous deposition of graphitic carbon on the hot graphite filament and of nanocrystalline diamond on a substrate facing the filament assembly is realized. In this paper the growth of nanocrystalline diamond films and their characterization (SEM, XRD, AFM) are presented. While the technique is promising for low cost, large area deposition of nanocrystalline diamond films, also the growth of microcrystalline diamond has been observed. 相似文献
83.
Lucas Andr Cavalcanti Brando Paola Maura Tricarico Rossella Gratton Almerinda Agrelli Luisa Zupin Haissam Abou-Saleh Ronald Moura Sergio Crovella 《International journal of molecular sciences》2021,22(4)
The high volume of information produced in the age of omics was and still is an important step to understanding several pathological processes, providing the enlightenment of complex molecular networks and the identification of molecular targets associated with many diseases. Despite these remarkable scientific advances, the majority of the results are disconnected and divergent, making their use limited. Skin diseases with alterations in the Notch signaling pathway were extensively studied during the omics era. In the GWAS Catalog, considering only studies on genomics association (GWAS), several works were deposited, some of which with divergent results. In addition, there are thousands of scientific articles available about these skin diseases. In our study, we focused our attention on skin diseases characterized by the impairment of Notch signaling, this pathway being of pivotal importance in the context of epithelial disorders. We considered the pathologies of five human skin diseases, Hidradenitis Suppurativa, Dowling Degos Disease, Adams–Oliver Syndrome, Psoriasis, and Atopic Dermatitis, in which the molecular alterations in the Notch signaling pathway have been reported. To this end, we started developing a new multiomics platform, PlatOMICs, to integrate and re-analyze omics information, searching for the molecular interactions involved in the pathogenesis of skin diseases with alterations in the Notch signaling pathway. 相似文献
84.
Alberto Di Renzo Francesco Paolo Di Maio Rossella Girimonte Brunello Formisani 《Powder Technology》2008,184(2):214-223
The distribution of solids in multicomponent fluidized beds strongly influences process performance, as undesired inhomogeneities usually result from a balance between the mixing and segregation tendencies. In the present work, a coupled DEM-CFD computational code is utilized to investigate on the equilibrium degree of mixing of two-component beds of particles with equal size and different density as function of the operating velocity and density ratio. Model validation is carried out first, by means of a direct comparison of simulated and experimental results on the mixing index and concentration profiles along the bed height, for a mixture of steel shots and glass ballotini of 433 μm average diameter. Since pseudo-2D geometry is used in simulations, the average voidage and the minimum fluidization conditions are very different from those of the experiments. Therefore, appropriate scaling of the velocity is necessary to compare the two systems. The DEM-CFD model is then utilized extensively to analyze the behaviour of the mixture at different velocities and varying component density ratio. A comprehensive data set is obtained for a dense-over-light density ratio ranging from 1 to 3 and a velocity ratio (actual over minimum fluidization velocity of the denser component) in the range 1 to 2. These results are re-examined within a unique framework by proposing a new model capable to interpret data while being mathematically and physically consistent with real observations. Inversion of this model provides a mixing map for the fluidized system whose behaviour is characterized for any combination of the two properties in the ranges investigated. 相似文献
85.
Daniela Guarnieri Annarita Falanga Ornella Muscetti Rossella Tarallo Sabato Fusco Massimiliano Galdiero Stefania Galdiero Paolo A. Netti 《Small (Weinheim an der Bergstrasse, Germany)》2013,9(6):853-862
Many therapeutic drugs are excluded from entering the brain due to their lack of transport through the blood–brain barrier (BBB). The development of new strategies for enhancing drug delivery to the brain is of great importance in diagnostics and therapeutics of central nervous diseases. To overcome this problem, a viral fusion peptide (gH625) derived from the glycoprotein gH of Herpes simplex virus type 1 is developed, which possesses several advantages including high cell translocation potency, absence of toxicity of the peptide itself, and the feasibility as an efficient carrier for delivering therapeutics. Therefore, it is hypothesized that brain delivery of nanoparticles conjugated with gH625 should be efficiently enhanced. The surface of fluorescent aminated polystyrene nanoparticles (NPs) is functionalized with gH625 via a covalent binding procedure, and the NP uptake mechanism and permeation across in vitro BBB models are studied. At early incubation times, the uptake of NPs with gH625 by brain endothelial cells is greater than that of the NPs without the peptide, and their intracellular motion is mainly characterized by a random walk behavior. Most importantly, gH625 peptide decreases NP intracellular accumulation as large aggregates and enhances the NP BBB crossing. In summary, these results establish that surface functionalization with gH625 may change NP fate by providing a good strategy for the design of promising carriers to deliver drugs across the BBB for the treatment of brain diseases. 相似文献
86.
Pezzolesi L Guerrini F Ciminiello P Dell'Aversano C Dello Iacovo E Fattorusso E Forino M Tartaglione L Pistocchi R 《Water research》2012,46(1):82-92
In the Mediterranean Sea, blooms of Ostreopsis cf. ovata and Ostreopsis siamensis have become increasingly frequent in the last decade and O. cf. ovata was found to produce palytoxin-like compounds (putative palytoxin, ovatoxin-a, -b, -c, -d and -e), a class of highly potent toxins. The environmental conditions seem to play a key role in influencing the abundance of Ostreopsis spp. High cell densities are generally recorded in concomitance with relatively high temperature and salinity and low hydrodynamics conditions. In this study the effects of temperature and salinity on the growth and toxicity of an Adriatic O. cf. ovata isolate were investigated. The highest growth rates of the Adriatic strain were recorded for cultures grown at 20 °C and at salinity values of 36 and 40, in accordance with natural bloom surveys. Toxicity was affected by growth conditions, with the highest toxin content on a per cell basis being measured at 25 °C and salinity 32.However, the highest total toxin content on a per litre basis was recorded at 20 °C and salinity 36, since under such conditions the growth yield was the highest.O. cf. ovata had lethal effects on Artemia nauplii and juvenile sea basses, and produced haemolysis of sheep erythrocytes. A comparison between haemolysis neutralization assay and HR LC-MS results showed a good correlation between haemolytic effect and total toxin content measured through HR LC-MS. Considering the increasing need for rapid and sensitive methods to detect palytoxin in natural samples, the haemolytic assay appears a useful method for preliminary quantification of the whole of palytoxin-like compounds in algal extracts. 相似文献
87.
Enrico Campioli Cecilia Rustichelli Rossella Avallone 《Journal of Functional Foods》2012,4(1):207-212
The effect of flaxseed oil rich in linolenic acid (ALA), and a mixed oil (flaxseed oil and fish oil) rich in eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), on the lipid clearance and peroxisome proliferator activated receptors (PPARs) in liver and adipose tissue of rats fed for 30 days with the two oils was evaluated. The results showed that after treatment with the mixed oil the hematic triacylglycerol content was significantly decreased compared to control animals. Regarding the tissue distribution of the major omega-3 fatty acids, both oils were able to increase ALA, EPA, docosapentaenoic acid (DPA) in liver and adipose tissue; and DHA solely in the adipose tissue. Finally the treatment with either flaxseed or mixed oil increased hepatic PPAR-γ expression but only the mixed oil enhanced the hepatic expression of PPAR-α. No effect on adipose tissue PPAR-γ expression was observed with both oils’ treatment. 相似文献
88.
Renzo Rossi Fabio Bellina Marco Lessi 《Advanced Synthesis \u0026amp; Catalysis》2012,354(7):1181-1255
The palladium‐catalyzed Suzuki–Miyaura reaction of multiply halogenated, electron‐rich and electron‐deficient heteroarenes is one of the most reliable and environmentally friendly tools for installing a wide range of non‐functionalized and functionalized carbon substituents onto heteroaromatic systems with exquisite chemo‐ and site‐selectivity. For substrates with different halogen groups the chemoselectivity of the Suzuki–Miyaura reactions has been found to be dependent on the reactivity difference between the halogens. However, the hardest achievement of selectivity in Suzuki–Miyaura monocouplings involving polyhalogenated heteroarenes with identical halogen atoms has been shown to be dominated by steric and electronic effects and the presence of directing groups at positions neighbouring the reaction sites. Moreover, in the case of symmetrically substituted dihaloheteroarenes with identical halogen atoms, highly selective monocoupling reactions have often been achieved only after a careful optimization of reaction parameters including the catalyst precursor, base, solvent, and the molar ratio between electrophile and organoboron reagent. This critical review with 341 references covers developments on the chemo‐ and site‐selective Suzuki–Miyaura monocoupling reactions of polyhalogenated heteroarenes with different or identical halogen atoms. It also includes the synthesis of polysubstituted heteroarenes, not easily accessible by other means, via consecutive monocoupling reactions and/or a more synthetically valuable approach involving one‐pot polycoupling reactions. 相似文献
89.
Fabio Affinito Rossella Brunetti Carlo Jacoboni Enrico Piccinini Massimo Rudan Albertino Bigiani Paolo Carloni 《Journal of Computational Electronics》2005,4(1-2):171-174
A physical model and a simulation framework are proposed for the analysis of conduction properties of ion channels. The permeation path of ions along the channel is defined through the simultaneous occupancy of a set of individual ion binding sites within the pore identified from structural X-ray data and Molecular Dynamics (MD) simulations. All permitted elementary transitions between different channel configurations and their rate constants can be evaluated from the atomistic structure and MD data and are implemented into a statistical model which is then coded in a Monte Carlo simulator. Results for K ions permeating the KcsA channel are shown. 相似文献
90.
Annarita Nappi Melania Murolo Serena Sagliocchi Caterina Miro Annunziata Gaetana Cicatiello Emery Di Cicco Rossella Di Paola Maddalena Raia Lucia DEsposito Mariano Stornaiuolo Monica Dentice 《International journal of molecular sciences》2021,22(13)
Thyroid hormones (THs) are key regulators of different biological processes. Their action involves genomic and non-genomic mechanisms, which together mediate the final effects of TH in target tissues. However, the proportion of the two processes and their contribution to the TH-mediated effects are still poorly understood. Skeletal muscle is a classical target tissue for TH, which regulates muscle strength and contraction, as well as energetic metabolism of myofibers. Here we address the different contribution of genomic and non-genomic action of TH in skeletal muscle cells by specifically silencing the deiodinase Dio2 or the β3-Integrin expression via CRISPR/Cas9 technology. We found that myoblast proliferation is inversely regulated by integrin signal and the D2-dependent TH activation. Similarly, inhibition of the nuclear receptor action reduced myoblast proliferation, confirming that genomic action of TH attenuates proliferative rates. Contrarily, genomic and non-genomic signals promote muscle differentiation and the regulation of the redox state. Taken together, our data reveal that integration of genomic and non-genomic signal pathways finely regulates skeletal muscle physiology. These findings not only contribute to the understanding of the mechanisms involved in TH modulation of muscle physiology but also add insight into the interplay between different mechanisms of action of TH in muscle cells. 相似文献