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451.
Cruz MC Sanz-Rodríguez F Zamarrón A Reyes E Carrasco E González S Juarranz A 《International journal of cosmetic science》2012,34(2):183-189
Regenerative properties of skin decrease with age, and thus, the search for substances that minimize cutaneous ageing has increased in the last few years. The secretion of the mollusc Cryptomphalus Aspersa (SCA) is a natural product that bears regenerative properties when applied topically. The purpose of this work is to study the in vitro effects of SCA on cell proliferation and migration, as well as on cell-cell (E-cadherin and β-catenin) and cell-substrate (vinculin and β1-integrin) adhesion proteins expression, using a human keratinocyte cell line (HaCaT cells) and primary dermal fibroblasts (HF). We tested the effects of SCA on cell proliferation using a colorimetric assay. In addition, SCA-induced changes on cell migration were studied by wound-healing assays. Besides, Western blot and immunofluorescence microscopy were carried out to test the expression of different cell adhesion proteins. We found that SCA promotes proliferation and migration of HaCaT cells in a time- and dose-dependent manner. Moreover, treatment with SCA increases the migratory behaviour and the expression of adhesion molecules in both HaCaT and HF. Finally, SCA also improves cell survival and promotes phosphorylation of FAK and nuclear localization of β-catenin. These results shed light on the molecular mechanisms underlying the regenerative properties of SCA, based on its promoting effect on skin cell migration, proliferation and survival. Moreover, these results support future clinical uses of SCA in the regeneration of wounded tissues. 相似文献
452.
Effect of olive ripeness on chemical properties and phenolic composition of chétoui virgin olive oil
Nabil Ben Youssef Wissem Zarrouk Alegría Carrasco‐Pancorbo Youssef Ouni Antonio Segura‐Carretero Alberto Fernández‐Gutiérrez Douja Daoud Mokhtar Zarrouk 《Journal of the science of food and agriculture》2010,90(2):199-204
BACKGROUND: The aim of the present work was to investigate the influence of fruit ripening on oil quality in an attempt to establish an optimum harvesting time for Chétoui olives, the second main olive variety cultivated in Tunisia. RESULTS: Our results showed that many analytical parameters, i.e., peroxide value, UV absorbance at 232 and 270 nm, chlorophyll pigments, carotenoids and oleic acid contents decreased during ripening, whilst oil content and linolenic acid increased. Free acidity remained practically stable with a very slight rise at the highest maturity index. The trend of oxidative stability, total phenols and o‐diphenols, showed an increase at the early stages followed by a reduction at more advanced stages of maturity. The major phenolic compounds, such as hydroxytyrosol, ligstroside aglycon, elenolic acid, acetoxy‐pinoresinol and oleuropein aglycon, seemed to have the same behaviour. In the case of tyrosol, a strong decrease was observed directly related with the ripening progress. CONLUSION: On the basis of the evolution of the analytical parameters studied, the best stage of Chétoui olive fruits for oil processing seems to be at ripeness index higher than 2.0 and lower than 3.0. Copyright © 2009 Society of Chemical Industry 相似文献
453.
Claudio B. Murta Tatiane K. Furuya Alexis G. M. Carrasco Miyuki Uno Laura Sichero Luisa L. Villa Sheila F. Faraj Rafael F. Coelho Giuliano B. Guglielmetti Mauricio D. Cordeiro Katia R. M. Leite William C. Nahas Roger Chammas Jos Pontes Jr. 《International journal of molecular sciences》2022,23(13)
Penile cancer (PeC) is a rare disease, and no prognostic biomarkers have been adopted in clinical practice yet. The objective of the present study was to identify differentially expressed miRNAs (DEmiRs) and genes (DEGs) as potential biomarkers for lymph node metastasis and other prognostic factors in PeC. Tumor samples were prospectively obtained from 24 patients with squamous cell carcinoma of the penis. miRNA microarray analysis was performed comparing tumors from patients with inguinal lymph node metastatic and localized disease, and the results were validated by qRT-PCR. Eighty-three gene expression levels were also compared between groups through qRT-PCR. Moreover, DEmiRs and DEGs expression levels were correlated with clinicopathological variables, cancer-specific (CSS), and overall survival (OS). TAC software, TM4 MeV 4.9 software, SPSS v.25.0, and R software v.4.0.2 were used for statistical analyses. We identified 21 DEmiRs in microarray analysis, and seven were selected for validation. miR-744-5p and miR-421 were overexpressed in tissue samples of metastatic patients, and high expression of miR-421 was also associated with lower OS. We found seven DEGs (CCND1, EGFR, ENTPD5, HOXA10, IGF1R, MYC, and SNAI2) related to metastatic disease. A significant association was found between increased MMP1 expression and tumor size, grade, pathological T stage, and perineural invasion. Other genes were also associated with clinicopathological variables, CSS and OS. Finally, we found changes in mRNA–miRNA regulation that contribute to understanding the mechanisms involved in tumor progression. Therefore, we identified miRNA and mRNA expression profiles as potential biomarkers associated with lymph node metastasis and prognosis in PeC, in addition to disruption in mRNA–miRNA regulation during disease progression. 相似文献
454.
The classic image processing method for flaw detection uses one image of the scene, or multiple images without correspondences
between them. To improve this scheme, automated inspection using multiple views has been developed in recent years. This strategy’s
key idea is to consider as real flaws those regions that can be tracked in a sequence of multiple images because they are
located in positions dictated by geometric conditions. In contrast, false alarms (or noise) can be successfully eliminated
in this manner, since they do not appear in the predicted places in the following images, and thus cannot be tracked. This
paper presents a method to inspect aluminum wheels using images taken from different positions using a method called automatic
multiple view inspection. Our method can be applied to uncalibrated image sequences, therefore, it is not necessary to determine
optical and geometric parameters normally present in the calibrated systems. In addition, to improve the performance, we designed
a false alarm reduction method in two and three views called intermediate classifier block (ICB). The ICB method takes advantage
of the classifier ensemble methodology by making use of feature analysis in multiple views. Using this method, real flaws
can be detected with high precision while most false alarms can be discriminated. 相似文献
455.
Log-modified Weibull regression models with censored data: Sensitivity and residual analysis 总被引:1,自引:0,他引:1
Jalmar M.F. Carrasco Gilberto A. Paula 《Computational statistics & data analysis》2008,52(8):4021-4039
This paper proposes a regression model considering the modified Weibull distribution. This distribution can be used to model bathtub-shaped failure rate functions. Assuming censored data, we consider maximum likelihood and Jackknife estimators for the parameters of the model. We derive the appropriate matrices for assessing local influence on the parameter estimates under different perturbation schemes and we also present some ways to perform global influence. Besides, for different parameter settings, sample sizes and censoring percentages, various simulations are performed and the empirical distribution of the modified deviance residual is displayed and compared with the standard normal distribution. These studies suggest that the residual analysis usually performed in normal linear regression models can be straightforwardly extended for a martingale-type residual in log-modified Weibull regression models with censored data. Finally, we analyze a real data set under log-modified Weibull regression models. A diagnostic analysis and a model checking based on the modified deviance residual are performed to select appropriate models. 相似文献
456.
G. Carucci F. Carrasco K. Trifoni M. Majone M. Beccari 《Canadian Metallurgical Quarterly》2005,131(7):1037-1045
Anaerobic treatability of two different wastes that represent the main refuse streams generated by a frozen food factory (fresh vegetable waste and precooked food waste) was assessed. Moreover, the sludge coming from agro-industrial wastewater treatment was codigested with the previously mentioned wastes. Batch tests were performed at different solids content both on the single wastes and on appropriate mixtures of them (also in order to simulate the seasonality of factory production). Both fresh vegetable and precooked food wastes strongly inhibited methanogenesis from unacclimated inoculum at 10% solids content (undiluted waste) and 5% solids content (eight- to nine-fold diluted waste), respectively. This was due to their high contents of potassium and lipids, respectively. The aerobic sludge from the wastewater treatment plant did not exert inhibitory effect up to 10% solids content (undiluted waste). Codigestion of the fresh vegetable waste and sludge (60 and 40% on wet basis) was more effective both in terms of rate and yield of methane production with respect to the single wastes (due to dilution and synergic effects). On the other hand, methanogenesis remained strongly inhibited from mixtures containing pre-cooked food waste (at 25 and 45%, on wet basis). Methanogenesis inhibition could be overcome by a long acclimation period. The results showed that fill-and-draw digestion in a 0.5 L lab-scale reactor of the fresh vegetable waste and sludge mixture after start up with acclimated inoculum allowed higher methane yields (37% at high organic load and 57% at low organic load). Better results were obtained in a 1.7 L micropilot fill-and-draw reactor (yield of 67%) fed at higher frequency. 相似文献
457.
Synchronization in parallel applications can be achieved either implicitly or explicitly. Implicit synchronization is typical of programming environments that provide predefined, and often simple, patterns of parallelism such as data-parallel libraries and languages and skeletal operations. Nevertheless, more flexible approaches that allow to express arbitrary task-level parallel computations without a predefined structure request in turn that the user explicitly specifies the synchronization needed among the parallel tasks. 相似文献
458.
Observer-based control for high order delayed systems with an unstable pole and a pole at the origin
Luis Alberto Barragan-Bonilla Juan Francisco Márquez-Rubio Basilio Del Muro Cuéllar Rocio Jasmin Vázquez-Guerra Claude Martínez 《Asian journal of control》2023,25(3):1759-1774
Time delays in dynamical systems are challenging when trying to control them. One of the most common techniques consists in estimating one or more signals of interest before they are delayed, in order to use them in the control stage. In this work, an observer-based control strategy for unstable linear systems with a pole at the origin and delay is suggested. Also, the proposed observer is extended to be used in the case of a high order unstable delayed system. Likewise, the conditions to ensure the existence of the proposed observer-predictor are presented. A methodology is introduced to obtain the observer parameters. The proposed observer scheme makes use of a Proportional-Integral-Derivative control that makes it possible to ensure the tracking of step-type references and the rejection of disturbances of the same type in the closed-loop system. 相似文献
459.
Gonzalo Abelln Jose A. Carrasco Eugenio Coronado Juan P. Prieto‐Ruiz Helena Prima‐García 《Advanced Materials Interfaces》2014,1(6)
The synthesis of ultrathin films (UTFs) of NiFe‐LDHs has been achieved by means of an in situ hydrothermal approach, leading to a flat disposition of the LDH crystallites on the substrate, in clear contrast to the most common perpendicular orientation reported to date. Experimental factors like time of synthesis or the nature of the substrate, seem to play a crucial role during the growing process. The 2D morphology of the NiFe‐LDH crystallites was kept after a calcination procedure, leading to a topotactic transformation into mixed‐metal oxide platelets. Hereby, in order to study the catalytic behavior of our samples, a chemical vapor deposition process is explored upon the as‐synthesized films. In presence of a carbon source (ethylene), these films catalyze a preferential low‐temperature (550 °C) growth of bamboo‐like carbon nanotubes, in stark contrast to the different mixture of carbon nanoforms obtained from the bulk samples. This work opens the door for the development of UTFs based on LDHs, which may be of utmost importance in a wide range of potential applications ranging from magnetic storage, catalysis or biomedical applications, to electrochemical batteries, anti‐corrosion and superhydrophobic coatings. 相似文献