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991.
R. Juncosa J. Delgado F. Padilla P. Rdgz-Vellando H. Hernández 《Mine Water and the Environment》2016,35(3):389-397
Seasonal increases in demand puts a strain on water supplies in the city of La Coruña (northwest Spain) and its surroundings during times of drought. Exploitation of Meirama Lake, a pit lake forming in a former lignite mine, could supplement the Abegondo-Cecebre reservoir, the city’s main water supply. We analysed the hydrochemistry and the Mero River basin regulations to determine whether the water quantity and quality could meet the needs during periods of increased demand and drought, and still satisfy ecological conditions required by law. Our results indicated that joint use of the two reservoirs is feasible. The local administration is implementing the recommendations by building a tunnel to tap into the pit lake. 相似文献
992.
In contrast with the information of the inspection body concerning the use of ronidazole, several non compliant muscle samples were detected using a liquid chromatography–tandem mass spectrometry (LC–MS/MS) method in accordance with confirmation criteria of Decision 2002/657/EC. This led to the suspicion that non compliance could be due to false positive results. In this context, a liquid chromatography–high resolution mass spectrometry (LC–HRMS) method was developed and sample extracts were re-analyzed, resolving the co eluting isobaric interfering peak, which also has an interfering product ion with the transition product (m/z 201 > 140). 相似文献
993.
Two chain models, a Gaussian chain and a touching-beads (wormlike) chain, are used to represent a flexible polyelectrolyte (sodium polystyrene sulfonate) and a semiflexible polyelectrolyte (sodium alginate), respectively. Monte Carlo and Brownian dynamics simulations of those models were carried out to obtain the ionic strength dependence of some conformational and hydrodynamic properties expressed in form of equivalent radii. Electrostatic interactions were taken into account by the Debye–Hückel potential, thus counterions are not considered explicitly. In the case of the sodium polystyrene sulfonate model, a linear dependence of the equivalent radii with the ionic strength is found for a region of intermediate to low enough ionic strength values, whereas for high values of the ionic strength the equivalent radii reach a plateau with a value equal to that of the uncharged chain. Thus, an extrapolation to infinite ionic strength of the linear region would not report the actual property value of the uncharged chain. In the case of the sodium alginate model such a linear dependence is not so clearly appreciated. Our simulation results show a good agreement with several experimental data which support the validity of the Debye–Hückel approximation to model different types of polyelectrolyte solutions in a simple way. 相似文献
994.
Contact breaking and Hertzian interactions between grains can both give rise to nonlinear vibrational response of static granular packings. We perform molecular dynamics simulations at constant energy in 2D of frictionless bidisperse disks that interact via Hertzian spring potentials as a function of energy and measure directly the vibrational response from the Fourier transform of the velocity autocorrelation function. We compare the measured vibrational response of static packings near jamming onset to that obtained from the eigenvalues of the dynamical matrix to determine the temperature above which the harmonic approximation breaks down. We compare packings that interact via single-sided (purely repulsive) and double-sided Hertzian spring interactions to disentangle the effects of the shape of the potential from contact breaking. Our studies show that while Hertzian interactions lead to weak nonlinearities in the vibrational behavior (e.g. the generation of harmonics of the eigenfrequencies of the dynamical matrix), the vibrational response of static packings with Hertzian contact interactions is dominated near jamming by contact breaking as found for systems with repulsive linear spring interactions. 相似文献
995.
Fibroblast Growth Factor-21 and the Beneficial Effects of Long-Chain n-3 Polyunsaturated Fatty Acids
Joan Villarroya Pavel Flachs Ibon Redondo-Angulo Marta Giralt Dasa Medrikova Francesc Villarroya Jan Kopecky Anna Planavila 《Lipids》2014,49(11):1081-1089
Long‐chain n‐3 polyunsaturated fatty acids (LC n‐3 PUFA) in the diet protect against insulin resistance and obesity. Fibroblast growth factor‐21 (Fgf21) is a hormonal factor released mainly by the liver that has powerful anti‐diabetic effects. Here, we tested whether the beneficial metabolic effects of LC n‐3 PUFA involve the induction of Fgf21. C57BL/6 J mice were exposed to an obesogenic, corn‐oil‐based, high‐fat diet (cHF), or a diet in which corn oil was replaced with a fish‐derived LC n‐3 PUFA concentrate (cHF + F) using two experimental settings: short‐term (3 weeks) and long‐term treatment (8 weeks). CHF + F reduced body weight gain, insulinemia, and triglyceridemia compared to cHF. cHF increased plasma Fgf21 levels and hepatic Fgf21 gene expression compared with controls, but these effects were less pronounced or absent in cHF + F‐fed mice. In contrast, hepatic expression of peroxisome proliferator‐activated receptor (PPAR)‐α target genes were more strongly induced by cHF + F than cHF, especially in the short‐term treatment setting. The expression of genes encoding Fgf21, its receptors, and Fgf21 targets was unaltered by short‐term LC n‐3 PUFA treatment, with the exception of Ucp1 (uncoupling protein 1) and adiponectin genes, which were specifically up‐regulated in white fat. In the long‐term treatment setting, the expression of Fgf21 target genes and receptors was not differentially affected by LC n‐3 PUFA. Collectively, our findings indicate that increased Fgf21 levels do not appear to be a major mechanism through which LC n‐3 PUFA ameliorates high‐fat‐diet‐associated metabolic disorders. 相似文献
996.
Derkacz Jan Leszczuk Mikołaj Grega Michał Koźbiał Arian Hernández Fernando Jorge Zorrilla Amaia Mendez García Zapirain Begoña Smaïli Kamel 《Multimedia Tools and Applications》2018,77(7):8359-8374
Multimedia Tools and Applications - In this paper, we will present a study concerning the understanding of the needs of people using Internet in order to access to multilingual information. In... 相似文献
997.
Aida Hernández-Arteaga José de Jesús Zermeo Nava Eleazar Samuel Kolosovas-Machuca J.Jesús Velázquez-Salazar Ekaterina Vinogradova Miguel José-Yacamán Hugo Ricardo Navarro-Contreras 《Nano Research》2017,(11):3662-3670
Breast cancer is the most common type of malignant tumor among women and their second leading cause of cancer-related deaths.The most common method for screening and diagnosis is mammography.Nonetheless,two main problems have been identified.First,the dose of radiation received during the test prevents the method from the use on women who are < 40 years old.Second,there can be mammogram failure owing to the lack of tumor contrast with the fibrous tissue.Therefore,there is a need for screening methods that will help to identify high-risk cases.We developed a biological marker test that can help to identify them.Increased levels of sialic acid (SA) in saliva are known to correlated with breast cancer.In this study,we evaluated the feasibility of Raman spectroscopy as a method for quantification of SA in saliva,using citrate-reduced silver nanoparticles (cit-Ag-NPs) as a surface-enhanced Raman spectroscopy (SERS) substrate.Quantification of SA was accomplished by measuring its intensity in saliva and comparing it with a calibration curve of SA standards.The mean SA concentration in saliva was found to be significantly higher among 100 breast cancer patients (18.3 ± 9.4 mg·dL-1;mean ± SD) than among 106 healthy controls (3.5 ± 1.0 mg·dL-1).The SERS test showed sensitivity of 94% and specificity 98% for detection of patients with breast cancer,assuming that SA concentration > 7 mg·dL-1 is a cutoff for positive test results.Our findings prove the usefulness of this SERS technique as a simple,convenient,and highly sensitive method of quantitative analysis of SA in saliva.The simplicity of this nanotechnological test may help to substantially reduce the mortality among patients with breast cancer by providing women with a simple,noninvasive screening test that can be applied regardless of age or density of breast tissue. 相似文献
998.
Ricardo Pérez-Rodríguez S. Jöns Arturo Hernández-Aguirre Carlos Alberto-Ochoa 《The International Journal of Advanced Manufacturing Technology》2014,73(1-4):3-21
The flexible jobshop scheduling problem permits the operation of each job to be processed by more than one machine. The idea is to assign the processing sequence of operations on the machines and the assignment of operations on machines such that the system objectives can be optimized. The assignment mentioned is a difficult task to implement on real manufacturing environments because there are many assumptions to satisfy, especially when the amount of work is not constant or sufficient to keep the manufacturing process busy for a long time, causing intermittent idle times. An estimation of distribution algorithm-based approach coupled with a simulation model is developed to solve the problem and implement the solution. Using the proposed approach, the shop performance can be noticeably improved when different machines are assigned to different schedules. 相似文献
999.
Arantza Sanvisens Neus Robert José María Hernández Paola Zuluaga Magí Farré Wifredo Coroleu Montserrat Serra Jordi Tor Robert Muga 《International journal of molecular sciences》2016,17(3)
Alcohol consumption in young women is a widespread habit that may continue during pregnancy and induce alterations in the fetus. We aimed to characterize prevalence of alcohol consumption in parturient women and to assess fetal ethanol exposure in their newborns by analyzing two direct metabolites of ethanol in meconium. This is a cross-sectional study performed in September 2011 and March 2012 in a series of women admitted to an obstetric unit following childbirth. During admission, socio-demographic and substance use (alcohol, tobacco, cannabis, cocaine, and opiates) during pregnancy were assessed using a structured questionnaire and clinical charts. We also recorded the characteristics of pregnancy, childbirth, and neonates. The meconium analysis was performed by liquid chromatography—tandem mass spectrometry (LC-MS/MS) to detect the presence of ethyl glucuronide (EtG) and ethyl sulfate (EtS). Fifty-one parturient and 52 neonates were included and 48 meconium samples were suitable for EtG and EtS detection. The median age of women was 30 years (interquartile range (IQR): 26–34 years); EtG was present in all meconium samples and median concentration of EtG was 67.9 ng/g (IQR: 36.0–110.6 ng/g). With respect to EtS, it was undetectable (<0.01 ng/g) in the majority of samples (79.1%). Only three (6%) women reported alcohol consumption during pregnancy in face-to-face interviews. However, prevalence of fetal exposure to alcohol through the detection of EtG and EtS was 4.2% and 16.7%, respectively. Prevention of alcohol consumption during pregnancy and the detection of substance use with markers of fetal exposure are essential components of maternal and child health. 相似文献
1000.
Luz Adriana Nicasio-Collazo Alexandra Delgado-González Ramón Casta?eda-Priego Enrique Hernández-Lemus 《Journal of the Royal Society Interface》2014,11(100)
DNA damage is one of the mechanisms of mutagenesis. Sequence integrity may be affected by the action of thermal changes, chemical agents, both endogenous and exogenous, and other environmental issues. Abnormally high mutation rates are referred to as genomic instability: a phenomenon closely related to the onset of cancer. Mutant genotypes may be able to confer some kind of selective advantage on subclonal cell populations, leading them to multiply until dominance in a localized tissue environment that later becomes the tumour. Cellular stress, especially that of oxidative and ionic nature, is a recognized trigger for DNA-damaging processes. A physico-chemical model has shown that high hysteresis rates in DNA denaturation curves may be indicative of dissipative processes inducing DNA damage, thus potentially leading to uncontrolled mutagenesis and genome instability. We here study selectively to what extent this phenomenon may occur by analysing the sequence length and composition effects on the thermodynamic behaviour and the presence of hysteresis in pressure-driven DNA denaturation; pronounced hysteresis in the denaturation/renaturation curves may indicate thermal susceptibility to DNA damage. In particular, we consider highly mutated regions of the genome characterized in diffuse large B-cell lymphoma on a recent whole exome next-generation sequencing effort. 相似文献