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1.
Background: Within the claudin (CLDN) family, CLDN12 mRNA expression is altered in various types of cancer, but its clinicopathological relevance has yet to be established due to the absence of specific antibodies (Abs) with broad applications. Methods: We generated a monoclonal Ab (mAb) against human/mouse CLDN12 and verified its specificity. By performing immunohistochemical staining and semiquantification, we evaluated the relationship between CLDN12 expression and clinicopathological parameters in tissues from 138 cases of cervical cancer. Results: Western blot and immunohistochemical analyses revealed that the established mAb selectively recognized the CLDN12 protein. Twenty six of the 138 cases (18.8%) showed low CLDN12 expression, and the disease-specific survival (DSS) and recurrence-free survival rates were significantly decreased compared with those in the high CLDN12 expression group. We also demonstrated, via univariable and multivariable analyses, that the low CLDN12 expression represents a significant prognostic factor for the DSS of cervical cancer patients (HR 3.412, p = 0.002 and HR 2.615, p = 0.029, respectively). Conclusions: It can be concluded that a reduced CLDN12 expression predicts a poor outcome for cervical cancer. The novel anti-CLDN12 mAb could be a valuable tool to evaluate the biological relevance of the CLDN12 expression in diverse cancer types and other diseases.  相似文献   
2.
Pactamycin is an antibiotic produced by Streptomyces pactum with antitumor and antimalarial properties. Pactamycin has a unique aminocyclitol core that is decorated with 3-aminoacetophenone, 6-methylsaliciate, and an N,N-dimethylcarbamoyl group. Herein, we show that the adenylation enzyme PctU activates 3-aminobenzoic acid (3ABA) with adenosine triphosphate and ligates it to the holo form of the discrete acyl carrier protein PctK to yield 3ABA-PctK. Then, 3ABA-PctK is N-glycosylated with uridine diphosphate-N-acetyl-d -glucosamine (UDP-GlcNAc) by the glycosyltransferase PctL to yield GlcNAc-3ABA-PctK. Because 3ABA is known to be a precursor of the 3-aminoacetophenone moiety, PctU appears to be a gatekeeper that selects the appropriate 3-aminobenzoate starter unit. Overall, we propose that acyl carrier protein-bound glycosylated 3ABA derivatives are biosynthetic intermediates of pactamycin biosynthesis.  相似文献   
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4.
ABSTRACT

Boron carbide (B4C) ceramics has many outstanding performance, such as extremely high hardness, low density, high melting point, high elastic modulus, high thermoelectromotive force, high chemical resistance, high neutron absorption cross section, high impact and excellent wear resistance. Therefore, B4C ceramics can be used in various industrial applications, such as lightweight ceramic armour, high temperature thermocouples, neutron absorber, reactor control rods in nuclear power engineering, polishing media for hard materials, abrasive media for lapping and grinding, and wear resistant components (blasting nozzles, die tips and grinding wheels). Pressureless sintering is the method with industrialised application value for B4C ceramics, however, it is impossible to sinter pure B4C ceramics to high densities without additives by pressureless sintering. So sintering additives must be used to promote the densification of B4C ceramics. The different sintering additives used to promote the densification of boron carbide will be described in this review, including carbon additives, metallic additives, oxide additives, non-oxide additives, combined additives and rare earth oxide additives. Finally, the recent research trends for sintering methods and sintering additives of B4C ceramics will also be proposed.  相似文献   
5.
Chronic infections are considered one of the most severe problems in skin wounds, and bacteria are present in over 90% of chronic wounds. Pseudomonas aeruginosa is frequently isolated from chronic wounds and is thought to be a cause of delayed wound healing. Invariant natural killer T (iNKT) cells, unique lymphocytes with a potent regulatory ability in various inflammatory responses, accelerate the wound healing process. In the present study, we investigated the contribution of iNKT cells in the host defense against P. aeruginosa inoculation at the wound sites. We analyzed the re-epithelialization, bacterial load, accumulation of leukocytes, and production of cytokines and antimicrobial peptides. In iNKT cell–deficient (Jα18KO) mice, re-epithelialization was significantly decreased, and the number of live colonies was significantly increased, when compared with those in wild-type (WT) mice on day 7. IL-17A, and IL-22 production was significantly lower in Jα18KO mice than in WT mice on day 5. Furthermore, the administration of α-galactosylceramide (α-GalCer), a specific activator of iNKT cells, led to enhanced host protection, as shown by reduced bacterial load, and to increased production of IL-22, IL-23, and S100A9 compared that of with WT mice. These results suggest that iNKT cells promote P. aeruginosa clearance during skin wound healing.  相似文献   
6.
Polymer-based nanohybrid materials were created using sustainable sepiolite clay composed from ubiquitous elements. Although sepiolite is generally recognized as a fibrous natural clay mineral, it turned out to be an acicular microcrystal because of the organo-modification of the outermost surface. Surface modification was performed using phosphonic acid derivatives containing hydrocarbon chains or fluorocarbon chains. Formation of a bidentate bond enhanced the desorption temperature and made nanocomposite preparation possible by melt compounding with polymers having a high melting point. As a result of organo-modification, amphiphilic sepiolite was obtained, and nanodispersion in an organic solvent was achieved. This technology was useful for detailed evaluation of sepiolite morphology. The nanocomposite of crystalline polymers/organo-modified sepiolites achieved uniform dispersion of these nanofillers in the matrix polymer. The introduction of 1 wt% nanofillers did not impair the transparency of the matrix polymer. As a result, a lamellae structure of the polymer developed, the crystallinity increased, and the mechanical properties improved. In addition, the crystallization temperature was improved, indicating that organo-modified sepiolites may act as a nucleating agent. It was found that sepiolite nanofiller with a highly aggregated tendency can achieve a well-nanodispersed state, even in phase-separable fluoropolymers, by applying fluorocarbon modification. POLYM. ENG. SCI., 60:541–552, 2020. © 2019 Society of Plastics Engineers  相似文献   
7.
In a previous paper, we proposed a novel linear synchronous motor with half‐wave‐rectified self‐excitation. A long‐stator‐type linear synchronous motor was built and its performance was verified by experiments. This paper presents a new current control method for the linear synchronous motor in order to achieve a wide range of speeds and high‐power operations. First, we propose a current control method for high‐thrust operation in the constant‐thrust region. This operation is realized by using the reluctance thrust resulting from the saliency of the linear synchronous motor. We also propose a control method that maximizes the ratio of the thrust to the voltage; this method can be used to expand the operating range. Wide‐range‐speed operation can be achieved by applying this new control method along with field‐weakening control. The thrust and operating characteristics of the proposed control methods are estimated by performing experiments and coupled electric and magnetic analysis.  相似文献   
8.
We have investigated the characteristics of radiated electromagnetic (EM) waves from positive and negative partial discharges (PD) in epoxy resin and cross‐linked polyethylene. We found that there is a correlation among the EM level from PD, the positive PD current, and electrical trees. Therefore, the growth of an electrical tree produces a lot of positive PD. We have also investigated the characteristics of the frequency region of EM waves from PD in air, insulating oil, and liquid epoxy in addition to the above insulators. EM waves were detected in the frequency region of 40 MHz to 300 MHz from positive and negative PD in epoxy resin and cross‐linked polyethylene. EM waves were also detected in the frequency region of 40 MHz to 150 MHz from positive and negative PD in air. In the case of insulating oil and liquid epoxy, EM waves were detected in the frequency regions of 40 MHz to 150 MHz from positive PD, and 40 MHz to 250 MHz from negative PD. The frequency region differed depending on the material and the discharge polarity. Our investigation indicates that the cause is differences in electric field strength at the time of PD occurrence.  相似文献   
9.
A simple interface fracture test for ceramic environmental barrier coatings (EBCs) on ceramic matrix composites (CMCs) was developed. A variation on the asymmetric double cantilever beam (ADCB) test was proposed so that the interface toughness could be measured in a small specimen of simple shape without applying interlaminar loading to the CMC substrate. The proposed test was applied to an EBC consisting of a mullite layer and Si bond coat on a monolithic SiC substrate. A pre-crack was introduced by pop-in cracking, and then a notch overlapping the pre-crack was machined. The pre-crack was opened by inserting a wedge into the notch. From the critical notch opening displacement the crack starts to propagate, interface toughness is calculated. The measured interface toughness was 4.1?J/m2. Finally, the application range of the test was discussed and suggestions were made for introduction of the notch and pre-crack.  相似文献   
10.
In this paper, photoresponsive behavior of multi-bilayered films having precisely controlled layer thickness prepared by stacking an azo-functionalized polymer liquid crystal, PMAzXAc, and polyvinyl alcohol alternatively, PVA, is described. The multi-bilayered films were found to reflect a light of specific wavelength depending on the layer thickness and refractive index, and showed the reversible change in the reflection intensity by irradiation with visible and UV lights. The change in the reflection intensity was brought about by change in the molecular orientation of PMAzXAc between an out-of-plane orientation and a photo-induced isotropic state, and was strongly dependent on the number of methylene spacer of PMAzXAc linking the azobenzene side group with the acrylate polymer main chain. PMAz6Ac with hexa-methylene spacer showed the largest change in the reflection intensity, while smaller change in the reflection intensity was observed for PMAzXAc having shorter or longer methylene spacer than 6. The effect of the methylene spacers on the photochemical change in the molecular orientation of azobenzene chromophores in the multi-bilayered films will be discussed.  相似文献   
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