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31.
32.
A Highly Planar Fluorinated Benzothiadiazole‐Based Conjugated Polymer for High‐Performance Organic Thin‐Film Transistors 下载免费PDF全文
33.
Won-Jun Jang Taekwon Son Sang-Hoon Song In Soo Ryu Sooyeun Lee Chul-Ho Jeong 《International journal of molecular sciences》2020,21(22)
Methamphetamine (MA) use disorder is a chronic neuropsychiatric disease characterized by recurrent binge episodes, intervals of abstinence, and relapses to MA use. Therefore, identification of the key genes and pathways involved is important for improving the diagnosis and treatment of this disorder. In this study, high-throughput RNA sequencing was performed to find the key genes and examine the comparability of gene expression between whisker follicles and the striatum of rats following MA self-administration. A total of 253 and 87 differentially expressed genes (DEGs) were identified in whisker follicles and the striatum, respectively. Multivariate and network analyses were performed on these DEGs to find hub genes and key pathways within the constructed network. A total of 129 and 49 genes were finally selected from the DEG sets of whisker follicles and of the striatum. Statistically significant DEGs were found to belong to the classes of genes involved in nicotine addiction, cocaine addiction, and amphetamine addiction in the striatum as well as in Parkinson’s, Huntington’s, and Alzheimer’s diseases in whisker follicles. Of note, several genes and pathways including retrograde endocannabinoid signaling and the synaptic vesicle cycle pathway were common between the two tissues. Therefore, this study provides the first data on gene expression levels in whisker follicles and in the striatum in relation to MA reward and thereby may accelerate the research on the whisker follicle as an alternative source of biomarkers for the diagnosis of MA use disorder. 相似文献
34.
Mina Han Ikue Abe Jihun Oh Jaehoon Jung Young Ji Son Jaegeun Noh Mitsuo Hara Takahiro Seki 《International journal of molecular sciences》2022,23(2)
Fluorescent molecular assembly systems provide an exciting platform for creating stimuli-responsive nano- and microstructured materials with optical, electronic, and sensing functions. To understand the relationship between (i) the plausible molecular structures preferentially adopted depending on the solvent polarity (such as N,N-dimethylformamide [DMF], tetrahydrofuran [THF], and toluene), (ii) the resulting spectroscopic features, and (iii) self-assembled nano-, micro-, and macrostructures, we chose a sterically crowded triangular azo dye (3Bu) composed of a polar molecular core and three peripheral biphenyl wings. The chromophore changed the solution color from yellow to pink-red depending on the solvent polarity. In a yellow DMF solution, a considerable amount of the twisted azo form could be kept stable with the help of favorable intermolecular interactions with the solvent molecules. By varying the concentration of the DMF solution, the morphology of self-assembled structures was transformed from nanoparticles to micrometer-sized one-dimensional (1D) structures such as sticks and fibers. In a pink-red toluene solution, the periphery of the central ring became more planar. The resulting significant amount of the keto-hydrazone tautomer grew into micro- and millimeter-sized 1D structures. Interestingly, when THF-H2O (1:1) mixtures were stored at a low temperature, elongated fibers were stacked sideways and eventually developed into anisotropic two-dimensional (2D) sheets. Notably, subsequent exposure of visible-light-irradiated sphere samples to solvent vapor resulted in reversible fluorescence off↔on switching accompanied by morphological restoration. These findings suggest that rational selection of organic dyes, solvents, and light is important for developing reusable fluorescent materials. 相似文献
35.
Tae Young Kong Siyoung Kim Youngju Lee Jung Kwon Son 《Journal of Nuclear Science and Technology》2019,56(8):764-769
Korean pressurized water reactors (PWRs) generally use radioactive effluent monitors for monitoring the concentration of radioactive effluents released to the environment. In this study, the operating margins for radioactive effluent monitors were analyzed to determine the levels of real-time concentration of effluents compared to effluent control limits (ECLs), the regulatory limits. The results show that the concentration of radioactive effluents released from Korean PWRs complied with the ECLs during the years 2012–2016. It was also found that outages at Korean PWRs did not impact the operating margins for radioactive effluent monitors; that is, there was no remarkable difference of the concentration of effluents between normal operation and maintenance periods. In terms of simultaneous effluent releases, the results demonstrate that exceeding the ECLs is unlikely to occur even under the hypothetical condition of coincident effluent releases from multiple discharge points at a Korean PWR. 相似文献
36.
Hong-Seok Son Geum-Sook Hwang Hyuk-Jin Ahn Won-Mok Park Cherl-Ho Lee Young-Shick Hong 《Food research international (Ottawa, Ont.)》2009,42(10):1483-1491
1H NMR spectroscopic analysis coupled with multivariate statistical data was used to characterize wines vinified from four grape varieties: Muscat Bailey A (Vitis labrusca), Campbell Early (V. labrusca B.), Kyoho (V. labrusca L.) and Meoru (Vitis coignetiae). Pattern recognition methods, such as principal component analysis (PCA) and orthogonal projection to latent structure discriminant analysis (OPLS-DA), showed clear differentiation between wines made from these grape varieties. Metabolites responsible for the differentiation were identified as 2,3-butanediol, glycerol, malate, citrate, tartrate, succinate, lactate, proline, alanine, choline and trigonelline. The PCA score plot of quantitative analysis of targeted profiling data also showed clear separation between the wines. The highest levels of glycerol, 2,3-butanediol, succinate and alcohol were found in Kyoho wines, suggesting higher sugar content in the Kyoho grape berry compared to other grape varieties. Higher contents of citrate and trigonelline in Muscat Bailey A wines, alanine in Campbell Early wines and proline, malate and choline in Meoru wines demonstrated that the metabolites of the wines vary with the grape variety. This study provides insight into the relationship between grape variety and its wine through global and targeted analysis of 1H NMR spectral data. 相似文献
37.
Changes in chemical stability and bioactivities of curcumin by ultraviolet radiation 总被引:1,自引:0,他引:1
Curcumin, a yellow pigment from turmeric (Curcuma longa), has shown various health beneficial effects. In the present study, changes in the chemical stability and bioactivities of curcumin by UV radiation were investigated. Curcumin degradation in water or phosphate buffered saline was accelerated under UV radiation (254 nm); the residual levels of curcumin were 36.9 and 16.8%, respectively, after 24 h radiation. Decomposition of curcumin by UV was more prominent at higher pHs. ABTS radical scavenging activity of curcumin after 24 h radiation was reduced significantly (p<0.05), whereas scavenging activities of DPPH radical and nitric oxide were not significantly changed (p>0.05) as compared to those of curcumin stored at a dark place. Stabilities and bioactivities of curcumin powder treated under UV radiation were, however, not significantly changed (p>0.05). The present results suggest that certain processing or storing conditions exposed to UV radiation could affect stability and bioactivities of curcumin. 相似文献
38.
Jalili M Jinap S Son R 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2011,28(4):485-493
The effect of 18 different chemicals, which included acidic compounds (sulfuric acid, chloridric acid, phosphoric acid, benzoic acid, citric acid, acetic acid), alkaline compounds (ammonia, sodium bicarbonate, sodium hydroxide, potassium hydroxide, calcium hydroxide), salts (acetate ammonium, sodium bisulfite, sodium hydrosulfite, sodium chloride, sodium sulfate) and oxidising agents (hydrogen peroxide, sodium hypochlorite), on the reduction of aflatoxins B(1), B(2), G(1) and G(2) and ochratoxin A (OTA) was investigated in black and white pepper. OTA and aflatoxins were determined using HPLC after immunoaffinity column clean-up. Almost all of the applied chemicals showed a significant degree of reduction on mycotoxins (p < 0.05). The lowest and highest reduction of aflatoxin B(1), which is the most dangerous aflatoxin, was 20.5% ± 2.7% using benzoic acid and 54.5% ± 2.7% using sodium hydroxide. There was no significant difference between black and white peppers (p < 0.05). 相似文献
39.
Kyoung‐Yong Chun Young Jun Son Sunghwan Jo Chang‐Soo Han 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(17)
A low‐powered and highly selective photomechanical sensor system mimicking stomata in the epidermis of leaves harvested from nature is demonstrated. This device uses a light‐responsive composite consisting of 4‐amino‐1,1′‐azobenzene‐3,4′‐disulfonic acid monosodium salt (AZO) and poly(diallyldimethylammonium chloride) (PDDA) coated on a membrane with tens of nanometer‐size pores. The ionic current change through the pore channels as a function of pore size variation is then measured. The tran–cis isomerism of AZO–PDDA during light irradiation and the operation mechanism of photomechanical ion channel sensor are discussed and analyzed using UV–vis spectroscopy and atomic force microscopy analysis. It presents the discriminative current levels to the different light wavelengths. The response time of the photoreceptor is about 0.2 s and it consumes very low operating power (≈15 nW) at 0.1 V bias. In addition, it is found that the change of the pore diameter during the light irradiation is due to the photomechanical effect, which is capable of distinguishing light intensity and wavelength. 相似文献
40.
So Gun-Baek Yi Hyun-Sik Son Yung-Deug Jin Gang-Gyoo 《International Journal of Control, Automation and Systems》2018,16(6):3047-3054
International Journal of Control, Automation and Systems - This paper presents two nonlinear PID (NPID) controllers which control the glycol temperature of a regasification system for LNG-fuelled... 相似文献