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991.
A Conjugate of an Anti‐Epidermal Growth Factor Receptor (EGFR) VHH and a Cell‐Penetrating Peptide Drives Receptor Internalization and Blocks EGFR Activation
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Sanne A. M. van Lith Dr. Dirk van den Brand Dr. Rike Wallbrecher Dr. Sander M. J. van Duijnhoven Dr. Roland Brock Dr. William P. J. Leenders 《Chembiochem : a European journal of chemical biology》2017,18(24):2390-2394
Overexpression of (mutated) receptor tyrosine kinases is a characteristic of many aggressive tumors, and induction of receptor uptake has long been recognized as a therapeutic modality. A conjugate of a synthetically produced cell‐penetrating peptide (CPP), corresponding to amino acids 38–59 of human lactoferrin, and the recombinant llama single‐domain antibody (VHH) 7D12, which binds the human epidermal growth factor receptor (EGFR), was generated by sortase A mediated transpeptidation. The conjugate blocks EGF‐mediated EGFR activation with higher efficacy than that of both modalities alone; a phenomenon that is caused by both effective receptor blockade and internalization. Thus, the VHH–CPP conjugate shows a combination of activities that implement a highly powerful new design principle to block receptor activation by its clearance from the cell surface. 相似文献
992.
地下工程研究的基本地学观点和原理 总被引:4,自引:1,他引:4
地下工程是典型的地质工程,所以地学在地下工程稳定性研究中具有重要意义。因此对地下工程研究的基本地学观点和原理予以讨论,着重分析了影响地下工程稳定性的基本地学要素、地下工程稳定性的优势面分析原理、量化评价模型以及地下工程治理的地质工程原理。 相似文献
993.
Eberhard Küster Falk Dorusch Bettina Meißner Holger Weiss Gerrit Schüürmann Rolf Altenburger 《Grundwasser》2003,8(1):32-40
The usage of an automatized and continuously (on-line) working biomonitor for the surveillance of groundwater remediation is presented and the data are compared to different discontinuous acute biotests. The use of an on-line biomonitor at the SAFIRA groundwater remediation testsite showed to be superior to the discontinuous tests. The long-time surveillance of two different remediation techniques revealed a decrease in remediation efficiency of one technique while the other technique -using activated carbon- did not show any reduction in efficiency. The validation of these results with other acute biotests (algae, fishembryo, daphnia and genotoxicity) indicated a complex groundwater contamination which can not be explained by the quantitatively main contaminant monochlorobenzene. It is suggested to use ecotoxicological biotests and knowledge in parallel to the conventional chemical analysis before a remediation strategy is designed. All anthropogenic contaminations (toxic or unwanted) should be identified beforehand such that the developed remediation techniques would be more target-oriented. 相似文献
994.
概述了台灣高鐵隧道的設計要求、沿線地質概況及岩體分類、典型地質之隧道施工方式、軟弱地質之輔助工法以及至2003年3月31日止的施工進度。 相似文献
995.
INFRASTRUCTURE PROVISION AND LOCATIONAL EFFICIENCY IN A FEDERATION: A NUMERICAL APPROACH 总被引:1,自引:0,他引:1
Dirk Dohse 《Papers in Regional Science》1998,77(3):241-263
ABSTRACT How do different strategies of infrastructure provision affect the spatial distribution of firms and households in a federation? The current article analyzes three polar cases: in the first case there is no publicly provided infrastructure at all. The second case is the case of uniform provision, i.e., a federal government provides the same amount of infrastructure to each region, regardless of the initial spatial distribution of firms, households, and tax revenues. The third strategy is decentralized provision, i.e., infrastructure is provided according to regional tax revenues. It is shown that the superior strategy depends on the initial distribution of firms among regions which may reflect historical accidence. 相似文献
996.
This paper describes how to optimize the energy performance of single-story multiple-skin facades (MSF) by changing the settings of the façades and HVAC-system according to the net energy demand of the building. The annual energy performance is analyzed for typical Belgian climatic conditions using a whole building simulation tool. Three MSF are scrutinised: a mechanically ventilated airflow window, a naturally ventilated double-skin façade and a mechanically ventilated supply window. Their performance is compared against the performance of two traditional facades: a traditional window with exterior and interior shading device. It is shown that both the heating and cooling demand may significantly be improved by implementing control strategies such as controlling the airflow rate and the recovery of air returning from the multiple-skin facades. 相似文献
997.
Tommy Y. Lo H.Z. Cui P.W.C. Tang H.C. Leung 《Construction and Building Materials》2008,22(7):1532-1535
This paper presents the mechanical properties of two bamboo species, namely Mao Zhu and Kao Zhu, which are commonly used for scaffolding in Southern China. Variations of the compressive strength against the physical properties of bamboo along the culms for both bamboo species were compared. A correlation of the average number of vascular bundle to the compressive strength of both bamboo species was developed. Findings indicate that the compressive strength of both Kao Zhu and Mao Zhu ranged between 45 and 65 N/mm2 and the compressive strength of top section bamboo was higher than the bottom section. The fibre area of the top section bamboo was also found to be greater than bottom section bamboo from microstructure count of the sclerenchyma fibre within the vascular bundle of bamboo section. The microscopic examination of sclerenchyma fibre of bamboo section can be an alternative measure of the strength of bamboo for construction use. 相似文献
998.
Analysis of bacterial diversity in river biofilms using 16S rDNA PCR-DGGE: methodological settings and fingerprints interpretation 总被引:5,自引:0,他引:5
Reliability of bacterial diversity assessment using polymerase chain reaction (PCR) denaturing gradient gel electrophoresis (DGGE) analysis of 16S rDNA fragments was evaluated for a particular complex microbial assemblage: river epilithic biofilm. By comparing 3 routine protocols on replicates of one river biofilm sample, we found that common DNA extraction procedures gave comparable diversity (from 28.0 to 30.7 bands detected) and community composition (> 75% of homology) despite differences in the total amount of extracted DNA (from 0.9 to 4.2 microg). Therefore methodological improvements only concerned electrophoretic separation of DNA fragments (range of denaturing gradient from 35% to 70% and migration time=18h) and standardisation of DNA amounts used (PCR-template=50 ng, gel loading=700 ng). Using such a standardised methodology we found a good reproducibility of all steps of the procedure. When an Escherichia coli strain was introduced as a contaminant in a biofilm sample, we were able to recover ribotypes from the strain. As concerns fields sampling, a satisfactory repeatability of banding patterns from neighbouring pebbles (sampling point) allowed discriminating between the biofilm intrasite variability (various points from a cross-profile). These trials confirmed that PCR-DGGE is suitable to assess a reliable genetic fingerprint of epilithic biofilms in the river. Phylogenetic analysis of 40 partial sequences of 16S rDNA from DGGE gels of two sets of river biofilms samples proved evidences for the retrieval of DNA fragments related to phototroph Eukarya. However, in both cases plastidial 16S rDNA represented less than 25% of the analysed operational taxonomic units. Taking into account that Cyanobacteria, as members of the Bacteria, were also detected, sequence analysis of relevant bands from the pattern is required to target "bacteria", i.e. the functional group of prokaryotic microorganisms to which one commonly refers as a key component in sustaining the nutrient turnover. 相似文献
999.
Kirk B. P. Shanks Steve N. G. Lo Brian Norton 《Journal of Housing and the Built Environment》2006,21(2):191-202
Extensive dynamic thermal simulation parametric analyses have been undertaken of energy efficient fabric alterations to social housing in Northern Ireland culminating in priorities for deployment. Five ȁ8basecaseȁ9 simulation models were used to represent the predominant characteristics of the existing social housing stock. The majority of technologies studied provided annual space-heating energy savings of more than 10%. The variation of energy savings and economic performance across the basecases highlights the value of a dwelling specific approach to selecting energy efficient building envelope technology solutions for energy rehabilitation programmes. The paper further outlines a framework for prioritising appropriate energy efficient building envelope technological solutions for a large regional building stock, i.e. existing social housing stock in Northern Ireland, highlighting influential parameters. An energy efficient building envelope inter-technology ranking approach provides a method of comparison across the various different dwellings in the regional housing stock. Airtightness ranked consistently highest across the dwellings studied with some solar technologies performing better than more technologically mature solutions such as insulation. 相似文献
1000.
Effects of iron surface pretreatment on sorption and reduction kinetics of trichloroethylene in a closed batch system 总被引:1,自引:0,他引:1
The decline of trichloroethylene (TCE) in a metallic iron-water system results from the combination of reduction reaction and sorption onto iron surfaces. Sorption, particularly by highly impure iron, accelerates the removal of TCE from the aqueous phase, but delays the prevalence of steady-state conditions. In this case, an overly high value of reaction rate constant in the design of a treatment system would be used. In this work, the effects of an iron surface with 8.0% C, 6.1% O and 0.8% Si separately following HCl-washing and H2-reducing pretreatment on sorption and reduction rates were examined. The amounts of both aqueous and sorbed TCE were measured using a modified solvent-extraction method. TCE sorption onto an iron surface, as quantified by the Langmuir sorption maximum, followed the trend H2-reduced Fe0 > HCl-washed Fe0 > untreated Fe0 (0.887, 0.365 and 0.311 mg/g, respectively). Measurements of the concentration of sorbed TCE revealed that about 34-37% of the initial mass of TCE in the aqueous phase was removed by sorption by H2-reduced Fe0, 16-19% was removed by HCl-washed Fe0 and 13-16% was removed by untreated Fe0. A combination of new and previously reported data on cast iron's capacity to sorb TCE revealed a linear relationship between this capacity and the C fraction in the surface of the iron, with the coefficient of determination (r2) exceeding 0.99. The first-order observed rate constants (k(obs)) of the reduction of TCE in contact with Fe0 were obtained from the slope of a plot of total TCE loss rate (-dC(T)/dt) versus the amount of TCE in the aqueous phase (C(w)) using linear least-squares analysis. The k(obs) values were 0.080, 0.148 and 0.191 h(-1) for untreated, HCl-washed and H2-reduced Fe0, respectively. Normalized to iron surface area concentration, the specific rate constants (k(SA)) were 2.3 7x 10(-3) , 2.31 x 10(-3) and 5.62 x 10(-3) h(-1) m(-2) L, respectively. The results indicated that HCl-washing approximately doubled k(obs), primarily because of the increase in the surface area of the iron, and it slightly decreased k(SA) due to rapid corrosion during the rinsing process. Both the number of reactive sites and the sorption capacity per unit iron surface area through the H2-reducing pretreatment were increased due to the reduction of iron oxide layer and the carbonization of carbon-containing subjects on the iron's surface. Hence, the H2 reduction of cast iron promotes the removal of TCE from contaminated water by the concurrent sorption and reduction. 相似文献