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41.
WALRUS: a similarity retrieval algorithm for image databases 总被引:2,自引:0,他引:2
Natsev A. Rajeev Rastogi Shim K. 《Knowledge and Data Engineering, IEEE Transactions on》2004,16(3):301-316
Approaches for content-based image querying typically extract a single signature from each image based on color, texture, or shape features. The images returned as the query result are then the ones whose signatures are closest to the signature of the query image. While efficient for simple images, such methods do not work well for complex scenes since they fail to retrieve images that match the query only partially, that is, only certain regions of the image match. This inefficiency leads to the discarding of images that may be semantically very similar to the query image since they may contain the same objects. The problem becomes even more apparent when we consider scaled or translated versions of the similar objects. We propose WALRUS (wavelet-based retrieval of user-specified scenes), a novel similarity retrieval algorithm that is robust to scaling and translation of objects within an image. WALRUS employs a novel similarity model in which each image is first decomposed into its regions and the similarity measure between a pair of images is then defined to be the fraction of the area of the two images covered by matching regions from the images. In order to extract regions for an image, WALRUS considers sliding windows of varying sizes and then clusters them based on the proximity of their signatures. An efficient dynamic programming algorithm is used to compute wavelet-based signatures for the sliding windows. Experimental results on real-life data sets corroborate the effectiveness of WALRUS'S similarity model. 相似文献
42.
When monocytes are stimulated with LPS (lipopolysaccharide) repeatedly then the initially high expression of the TNF (tumor necrosis factor) gene is only very low, i.e. the cells are tolerant to LPS. Tolerant cells still express the CD14 receptor and they can still be activated to mobilize NF-kappa B into nucleus. Analysis of the binding proteins employing the -605 motif of the human TNF promoter (GGGGCTGTCCC) revealed that in tolerant cells of the human monocytic cell line Mono Mac 6 there is a predominance of p50p50 of NF-kappa B. We now show that a mutant motif that exchanges the terminal 3' C for a G fails to bind the p50 homodimer that is upregulated in LPS toler ant human Mono Mac 6 cells. The same is true for nuclear extracts taken from the murine P388D1 macrophage cell line when tested with the -516 motif of the murine TNF promoter (GGGGGCTTTCCC). Here the wild type motif gives efficient binding of p50p50 that again is upregulated in tolerant cells whereas a mutant with a 3' G shows hardly any binding of p50p50. Conversely, the murine kappa light chain enhancer motif (GGGGACTTTCCG) does not efficiently bind the nuclear p50p50 from tolerant murine P388 macrophages. Binding is, however, readily detected when the 3' G is replaced by a C. These data show that the detection of upregulated p50 homodimers in LPS tolerant cells is dependent on subtle differences in the sequence of the DNA binding motif. 相似文献
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Surya V. Prabhakar Vattikuti Jie Zeng Rajavaram Ramaraghavulu Jaesool Shim Alain Mauger Christian M. Julien 《International journal of molecular sciences》2023,24(1)
Bismuth-based nanostructures (BBNs) have attracted extensive research attention due to their tremendous development in the fields of photocatalysis and electro-catalysis. BBNs are considered potential photocatalysts because of their easily tuned electronic properties by changing their chemical composition, surface morphology, crystal structure, and band energies. However, their photocatalytic performance is not satisfactory yet, which limits their use in practical applications. To date, the charge carrier behavior of surface-engineered bismuth-based nanostructured photocatalysts has been under study to harness abundant solar energy for pollutant degradation and water splitting. Therefore, in this review, photocatalytic concepts and surface engineering for improving charge transport and the separation of available photocatalysts are first introduced. Afterward, the different strategies mainly implemented for the improvement of the photocatalytic activity are considered, including different synthetic approaches, the engineering of nanostructures, the influence of phase structure, and the active species produced from heterojunctions. Photocatalytic enhancement via the surface plasmon resonance effect is also examined and the photocatalytic performance of the bismuth-based photocatalytic mechanism is elucidated and discussed in detail, considering the different semiconductor junctions. Based on recent reports, current challenges and future directions for designing and developing bismuth-based nanostructured photocatalysts for enhanced photoactivity and stability are summarized. 相似文献
45.
Ji Hyun Lee Ji Woong Kim Ha Rim Yang Seong-Won Song Song-Jae Lee Yeongha Jeon Anna Ju Narim Lee Min-Gu Kim Minjoo Kim Kyusang Hwang Jin Hwan Yoon Hyunbo Shim Sukmook Lee 《International journal of molecular sciences》2022,23(13)
Small-cell lung cancer (SCLC) is the most aggressive form of lung cancer and the leading cause of global cancer-related mortality. Despite the earlier identification of membrane-proximal cleavage of cell adhesion molecule 1 (CADM1) in cancers, the role of the membrane-bound fragment of CAMD1 (MF-CADM1) is yet to be clearly identified. In this study, we first isolated MF-CADM1-specific fully human single-chain variable fragments (scFvs) from the human synthetic scFv antibody library using the phage display technology. Following the selected scFv conversion to human immunoglobulin G1 (IgG1) scFv-Fc antibodies (K103.1–4), multiple characterization studies, including antibody cross-species reactivity, purity, production yield, and binding affinity, were verified. Finally, via intensive in vitro efficacy and toxicity evaluation studies, we identified K103.3 as a lead antibody that potently promotes the death of human SCLC cell lines, including NCI-H69, NCI-H146, and NCI-H187, by activated Jurkat T cells without severe endothelial toxicity. Taken together, these findings suggest that antibody-based targeting of MF-CADM1 may be an effective strategy to potentiate T cell-mediated SCLC death, and MF-CADM1 may be a novel potential therapeutic target in SCLC for antibody therapy. 相似文献
46.
Won‐Bo Shim Jeong‐Sook Kim Min‐Gon Kim Duck‐Hwa Chung 《Journal of food science》2013,78(10):M1575-M1581
A rapid immunochromatographic (ICG) strip based on a conjugate of colloidal gold and monoclonal antibody (mAb) was developed for the rapid, sensitive, and on‐site detection of sulfamethazine in meat and egg samples. The detection limit of the ICG strip is 2 ng/mL, and the assay can be completed in 10 min. A cross‐reactivity test indicated that the ICG strip was highly specific to sulfamethazine with no cross‐reaction with sulfonamide compounds and other antibiotics. The results of the recovery test from meat and egg samples spiked with sulfamethazine were in good agreement with those obtained by the indirect competitive enzyme‐linked immunosorbent assay. These results demonstrated that the ICG strip can be used as a rapid and qualitative tool for on‐site screening of sulfamethazine in meat and egg samples. 相似文献
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ABSTRACT: Canned tuna ( n = 240), salmon ( n = 16), and mackerel ( n = 16) were analyzed for mercury and fatty acids. Average mercury levels were 188, 45, and 55 ppb, respectively, and below the FDA Action Level of 1000 ppb. "Light tuna in water" contained lower mercury (x = 54 ppb) compared with "white/albacore tuna in water," which contained higher eicosapentaenoic acid/docosahexaenoic acid (EPA/DHA) x= 711 mg/100 g wet tissue). Mercury residues in salmon (x = 45 ppb) and mackerel (x = 55 ppb) were lower than in tuna products, but the EPA/DHA levels were higher (salmon, ×= 1623 mg/100 g wet tissue; mackerel, ×= 851 mg/100 g wet tissue). Information from this study will help women of childbearing age to limit their intake of mercury while obtaining healthy fats from fish. 相似文献
49.
Sunhye Yang Kamrun Nahar Fatema Ick-Jun Kim Jihyeon Ryu Sang Eun Shim Won-Chun Oh 《Advanced Powder Technology》2021,32(4):1116-1126
This paper reports the synthesis of various molar concentrations of manganese (Mn)-doped Ultra-High Surface area Activated Carbon (USAC) additives and their efficient use as cathode materials for supercapacitors. We synthesized the nanoparticles via a novel and facile dip-coating process and characterized them in detail by various analytical techniques. The SEM, EDAX, and XPS results showed that the Mn ions were successfully substituted on the USAC additives’ layered structure without any structural changes. The long cyclic stability of the as-prepared Mn-doped USAC additives was tested as a cathode material for supercapacitors at different current densities. The detailed experimental results showed that the Mn dopant content crucially determines the electrochemical performances of the USAC additives. Electrochemical measurements showed that the MnCEP-S600HTT with 0.10 mol% molar concentration of Mn dopant gives the best cycling performances. It delivers a discharge capacity of 262.9 mAh g?1 after 100 cycles. Further increasing the current density to 1000 mA g?1 allowed it to still maintain 253.6 mAh g?1 after 200 cycles. We confirmed that the structure of Mn-doped USAC additives is an important pole to improve the structural stability and electrochemical properties. 相似文献
50.
Jae‐Hwan Chung Sol Kim Sang‐Jun Lee Jin‐Oh Chung Yu‐Jin Oh Soon‐Mi Shim 《Journal of food science》2013,78(5):C685-C690
The effect of green tea formulated with vitamin C and xylitol on intestinal cell transport of gallated and nongallated catechin was studied. The transport of catechins from both apical to basolateral and basolateral to apical directions was measured. The effect of vitamin C (4, 10, 20 ppm), xylitol (11, 27.5, 55 ppm), and combinations of both on the intestinal transport rate of catechins was examined. The efflux value (Pb→a/Pa→b) of (–)‐epigallocatechin (EGC), (–)‐epigallocatechin gallate (EGCG), (–)‐epicatechin (EC), and (–)‐epicatechin gallate (ECG) was 0.26, 0.22, 1.22, and 0.17, respectively, indicating that EC appeared to be less absorbed compared with other catechins. The addition of xylitol (11, 27.5, 55 ppm) and vitamin C (4, 10, 20 ppm) and in combination enhanced transport rate of nongallated catechins such as EC and EGC. For EC, vitamin C was revealed to be the most effective on intestinal transport, implying the inhibition of the efflux transport mechanism of EC. Intestinal transport of gallated catechins significantly increased from catechins formulated with vitamin C and xylitol in a dose‐dependent manner compared to the catechin‐only formulation. Results provide a potential strategy to enhance the delivery and bioavailability of catechins in humans by modulating green tea formulation with vitamin C and xylitol. 相似文献