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91.
Three studies examined the following hypotheses for the relation of subjective well-being (SWB) with memory for positive versus negative life events: (1) differences in retrieval mood, (2) the incidence of positive and negative events, (3) the interpretation of events, and (4) frequency of rehearsal. In Studies 1 (n?=?420) and 2 (n?=?94), the partial correlation of retrieval mood with recall, controlling for SWB, was trivial, suggesting that mood had little or no effect on recall. Endorsement frequencies of positive minus negative concrete events and interpretive events on checklists in Studies 2 and 3 each correlated with SWB (ps? 相似文献
92.
93.
Correlation coefficient mapping has been applied to intrinsic fluorescence spectra of colonic tissue for the purpose of cancer diagnosis. Fluorescence emission spectra were collected of 57 colonic tissue sites in a range of 4 physiological conditions: normal (29), hyperplastic (2), adenomatous (5), and cancerous tissues (21). The sample-sample correlation was used to examine the ability of correlation coefficient mapping to determine tissue disease state. The correlation coefficient map indicates two main categories of samples. These categories were found to relate to disease states of the tissue. Sensitivity, selectivity, predictive value positive, and predictive value negative for differentiation between normal tissue and all other categories were all above 92%. This was found to be similar to, or higher than, tissue classification using existing methods of data reduction. Wavelength-wavelength correlation among the samples highlights areas of importance for tissue classification. The two-dimensional correlation map reveals absorption by NADH and hemoglobin in the samples as negative correlation, an effect not obvious from the one-dimensional fluorescence spectra alone. The integrity of tissue was examined in a time series of spectra of a single tissue sample taken after tissue resection. The wavelength-wavelength correlation coefficient map shows the areas of significance for each fluorophore and their relation to each other. NADH displays negative correlation to collagen and FAD, from the absorption of emission or fluorescence resonance energy transfer. The wavelength-wavelength correlation map for the decay set also clearly shows that there are only three fluorophores of importance in the samples, by the well-defined pattern of the map. The sample-sample correlation coefficient map reveals the changes over time and their impact on tissue classification. Correlation coefficient mapping proves to be an effective method for sample classification and cancer detection. 相似文献
94.
We report the irreversible bleaching characteristics of 4-(dicyanomethylene)-2-methyl-6-(p-dimethyl aminostyryl)-4H-pyran (DCM) doped into perfluorocyclobutene (PFCB) and a new material known as DH-6 doped into amorphous polycarbonate (APC) by a monochromatic bleaching source. The wavelength dependent rate constants for the irreversible bleaching process are found, and the experimental bleaching characteristics are compared to the theoretical bleaching characteristics determined from a kinetic model of the bleaching process. 相似文献
95.
96.
Danyluk MD Interiano Villeda LO Friedrich LM Schneider KR Etxeberria E 《Journal of food protection》2010,73(12):2276-2280
The survival-growth capacity of Salmonella populations on tomato epidermis labeled by a natural-light labeling system was investigated after persistent fears of such marks serving as possible entryways for the pathogenic organisms, alone and in the presence of Pectobacterium carotovorum subsp. carotovorum, a soft-rot organism. Different treatments involving natural-light labeling, fruit waxing, and a five-strain cocktail of Salmonella were applied to mature green tomato surfaces in different sequences prior to storage at 4, 12, or 25°C. Fruit was sampled every 3 days, and Salmonella was enumerated from all treatments and unlabeled fruit, which served as controls. There were no significant differences between treatments or between treatments and controls throughout. The results indicate that the cuticle and epidermal interruptions caused by natural-light labeling do not facilitate the penetration and colonization of the tomato pericarp. In a separate set of experiments, the capacity of Salmonella to penetrate tomato in the presence of a potential synergism with P. carotovorum subsp. carotovorum was investigated. The addition of P. carotovorum at higher, lower, or equal population densities to Salmonella did not significantly alter the behavior of Salmonella on tomatoes stored at 25°C, regardless of natural-light labeling. The inability of P. carotovorum and Salmonella to colonize natural-light-etched surfaces of tomato fruit indicates that the use of this technology does not adversely compromise the surface of tomatoes. 相似文献
97.
Gary E. Bulman Ed Siivola Ryan Wiitala Rama Venkatasubramanian Michael Acree Nathan Ritz 《Journal of Electronic Materials》2009,38(7):1510-1515
Thin-film Bi2Te3- and Sb2Te3-based superlattice (SL) thermoelectric (TE) devices are an enabling technology for high-power and low-temperature applications,
which include low-noise amplifier cooling, electronics hot-spot cooling, radio frequency (RF) amplifier thermal management,
and direct sensor cooling. Bulk TE devices, which can pump heat loads on the order of 10 W/cm2, are not suitable in these applications due to their large size and low heat pumping capacity. Recently, we have demonstrated
an external maximum temperature difference, ΔT
max, as high as 58 K in an SL thin-film p–n couple. This state-of-the-art couple exhibited a cold-side minimum temperature, T
cmin, of −30.9°C. We regularly attain ΔT
max values in excess of 53 K, in spite of the many significant electrical and thermal parasitics that are unique to thin-film
devices. These measurements do not use any complex thermal management at the heat sink to remove the heat flux from the TE
device’s hot side. We describe here multistage SL cooling technologies currently being developed at RTI that can provide useful
microcooling cold-side temperatures of 200 K. This effort includes a three-stage module employing independently powered stages
which produced a ΔT
max of 101.6 K with a T
cmin of −75°C, as well as a novel two-wire three-stage SL cascade which demonstrated a T
cmin of −46°C and a ΔT
max of nearly 74 K. These RTI modules are only 2.5 mm thick, significantly thinner than a similar commercial three-stage module
(5.3 mm thick) that produces a ΔT
max of 96 K. In addition, TE coolers fabricated from these thin-film SL materials perform significantly better than the extrapolated
performance of similar thickness bulk alloy materials. 相似文献
98.
Monique van Scherpenzeel Ed E. Moret Dr. Lluis Ballell Dr. Rob M. J. Liskamp Prof. Dr. Ulf J. Nilsson Dr. Hakon Leffler Dr. Roland J. Pieters Dr. 《Chembiochem : a European journal of chemical biology》2009,10(10):1724-1733
Light up galectin: Photoprobes based on thiodigalactoside were prepared for galectin‐3, a lectin linked to cancer. The probes contained either benzophenone or acetophenone moieties as the photolabel for covalent attachment to the protein. One particular probe labeled galectin‐3 selectively, even in the presence of cell lysate.
99.
《城市公用事业》编辑部 《城市公用事业》2009,23(5):I0001-I0001
节能减排是指节约能源和减少环境有害物排放。中国“十一五”规划纲要提出,“十一五”期间单位国内生产总值能耗降低20%左右,主要污染物排放总量减少10%。这是贯彻落实科学发展观、构建社会主义和谐社会的重大举措;是建设资源节约型、环境友好型社会,推进经济结构调整,转变增长方式的必由之路。节能减排工作也渗透于城市公用事业发展的各个方面。 相似文献
100.
Giovanna Gomes Lara Gracielle Ferreira Andrade Marcelo Fernandes Cipreste Wellington Marcos da Silva Pedro Lana Gastelois Dawidson Assis Gomes Marcelo Coutinho de Miranda Waldemar Augusto de Almeida Macedo Maria Jose Neves Edésia Martins Barros de Sousa 《Journal of materials science. Materials in medicine》2018,29(8):130
The development of a myriad of nanoparticles types has opened new possibilities for the diagnostics and treatment of many diseases, especially for cancer. However, most of the researches done so far do not focus on the protection of normal cells surrounding a tumor from irradiation bystander effects that might lead to cancer recurrence. Gap-junctions are known to be involved in this process, which leads to genomic instability of neighboring normal cells, and flufenamic acid (FFA) is included in a new group of gap-junction blockers recently discovered. The present work explores the use of mesoporous silica nanoparticles MCM-41 functionalized with 3-Aminopropyltriethoxysilane (APTES) for anchoring the flufenamic acid for its prolonged and controlled release and protection from radiation bystander effects. MCM-41 and functionalized samples were structurally and chemically characterized with multiple techniques. The biocompatibility of all samples was tested in a live/dead assay performed in cultured MRC-5 and HeLa cells. HeLa cells cultured were exposed to 50?Gy of gamma-rays and the media transferred to fibroblast cells cultured separately. Our results show that MCM-41 and functionalized samples have high biocompatibility with MCR-5 and HeLa cells, and most importantly, the FFA delivered by these NPs was able to halt apoptosis, one of main bystander effects. 相似文献