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排序方式: 共有439条查询结果,搜索用时 15 毫秒
91.
Janne Pesonen Toivo Kuokkanen Erik Kaipiainen Juha Koskela Iina Jerkku Ari Pappinen Aki Villa 《Holz als Roh- und Werkstoff》2014,72(6):769-777
The European Union’s growth strategy (Europe 2020) requires reductions in greenhouse gas (GHG) emissions and increases in both renewable energy sources and energy efficiency. Short rotation forestry (SRF) has achieved greater awareness due to these targets. Short rotations (1–12 years), rapid growth and the ability to coppice are typical for SRF. Salix, Populus, Alnus and Betula have smaller GHG emissions of biomass production than annual agricultural plant species, since management and harvesting are not needed every year. Physicochemical properties of these species must be known when their utilisation is planned and optimised. Seven tree species were studied: three willows (Salix myrsinifolia, Salix schwerinii and Klara), one aspen (Populus tremula), one alder (Alnus glutinosa) and two birches (Betula pendula and Betula pubescens). One stem wood (S) sample and one stem wood and bark (SB) sample of each tree were investigated. Furthermore, seven surface soil samples and four incineration ash samples (two S. myrsinifolia and two S. schwerinii) were also studied. Heating values, densities, ash contents as well as carbon, hydrogen and nitrogen contents of all short rotation biomass samples were usually quite typical for the corresponding tree species. Additional observations included the accumulation of cadmium in willow and aspen samples, small chloride content values, and higher ash- and element contents in SB samples than in the corresponding S samples. Nutrient content of ash was usually higher in the S sample, contradictory to biomass samples, and finally the cadmium content of the ash samples was very high. 相似文献
92.
Lyes Tabet Cyrill Bussy Ari Setyan Angélique Simon-Deckers Michel J Rossi Jorge Boczkowski Sophie Lanone 《Particle and fibre toxicology》2011,8(1):3
Background
carbon nanotubes (CNT) can have adverse effects on health. Therefore, minimizing the risk associated with CNT exposure is of crucial importance. The aim of this work was to evaluate if coating multi-walled CNT (MWCNT) with polymers could modify their toxicity, thus representing a useful strategy to decrease adverse health effects of CNT. We used industrially-produced MWCNT uncoated (NT1) or coated (50/50 wt%) with acid-based (NT2) or polystyrene-based (NT3) polymer, and exposed murine macrophages (RAW 264.7 cell line) or Balb/c mice by intratracheal administration. Biological experiments were performed both in vitro and in vivo, examining time- and dose-dependent effects of CNT, in terms of cytotoxicity, expression of genes and proteins related to oxidative stress, inflammation and tissue remodeling, cell and lung tissue morphology (optical and transmission electron microscopy), and bronchoalveolar lavage fluid content analysis. 相似文献93.
94.
95.
Through microcalorimetric experiments, disperse order (DO) dissolution kinetics in preannealedα-Cu-Al alloys containing 19, 13 and 6.5 at % aluminium were adequately described by the integrated kinetic model function
arising from the steady-state part of the diffusion field:f(y)=1 − (1−y) 2/3. Domain sizes after the annealing treatment, and also critical radii, were determined from differential scanning calorimetry
data analysis at different heating rates. The existence of critical radii indicates that the disperse-order dissolution process
is a first-order transition. Nevertheless, it was inferred that for very dilute alloys, only short-range order is present.
After pre-annealing the alloys at different temperatures, volume fractions and domain concentrations were computed by employing
the above kinetic model under high heating-rate conditions. On the basis of appropriate time constant and diffusion time calculations,
the range of such temperatures compatible with equilibrium attainment was established. Prolonged pre-anneals alter the particle
distribution, but do not influence either volume fractions or domain sizes. A semi-quantitative particle radius-particle concentration-temperature
diagram was proposed forα-Cu-Al alloys. 相似文献
96.
JM Cuesta Presedo C Rioja Sanz J Benejam Gual P Gil Martínez A Bono Ari?o LA Rioja Sanz 《Canadian Metallurgical Quarterly》1997,21(6):624-627
Infantile myofibromatosis is a rare disease characterized by myofibroblastic proliferation, and typically occurs in early infancy. There is a wide spectrum of clinical presentation, which may involve various kinds of tissues in the body. Skin and subcutaneous lesions were the types of tissue most often seen. Although a multicentric form may behave aggressively, a solitary form of the tumor is benign with the possibility of spontaneous regression. Conservative management is justified after proper pathological diagnosis if the tumor involves an aesthetically important area. A case of solitary infantile myofibromatosis involving the upper lip is presented. Partial excision for biopsy was performed and long-term observation was undertaken. The tumor disappeared 3 years postoperatively. 相似文献
97.
Overpressure capacity of a box type concrete containment structure is evaluated. Plastic analysis of the finite element model is performed using a quadrilateral plate element of homogeneous material. A special approach is used to represent nonlinear properties of reinforced concrete, such as concrete cracking and crushing and steel yielding. Those properties are represented by a set of idealized stress-strain curves of equivalent homogeneous sections.The analysis allows for a better estimate of the overpressure capacity of the containment structure while keeping the computer cost low by avoiding the use of the more expensive reinforced concrete brick element. 相似文献
98.
Ari Jaaksi 《Software》1995,25(11):1203-1221
This paper presents an object-oriented approach for the specification of graphical user interfaces. Specification starts with the analysis of the end user's operations. The user interface is then designed on the basis of this analysis. Operation analysis is followed by structure and component specification which presents the dialogue structure of the application and the contents of each dialogue. Visualization produces the final screen layouts, and task specification documents the usage of the user interface for the purpose of creating user's guides. The method presented in this paper makes it easier for a designer to take the end user's needs into account. Still, it does not automatically guarantee good quality user interfaces. The top-down nature of the method allows the designer to concentrate on the most important aspects of the user interface and split the design procedure into manageable pieces. Also, the visibility of the process allows the designer to communicate with other people while specifying the user interface. This paper connects the method with the object-oriented specification of entire applications. It briefly explains the connections with object-oriented analysis and design, and demonstrates how to implement the specified user interface in an object oriented fashion. The approach presented in this paper is being applied in the development of a large network management system with about two million lines of C++ code running in the XII environment. Still, the method does not require the specification being implemented with any specific windowing system. The only requirement is that the user interface is based on graphical elements, such as dialogues, push-buttons and text fields. 相似文献
99.
100.
D Ardissino PA Merlini R Ari?ns R Coppola E Bramucci PM Mannucci 《Canadian Metallurgical Quarterly》1997,349(9054):769-771
BACKGROUND: Coronary atherosclerotic-plaque thrombosis is a key event in the pathogenesis of unstable angina and myocardial infarction. Although plaque rupture or fissuring frequently occurs in atherosclerosis, only a small proportion of ruptured plaques develop thromboses. METHODS: Tissue-factor antigen and activity were measured in atherectomy samples from 50 consecutive patients with coronary artery disease (stable angina n = 19, unstable angina n = 24, and myocardial infarction n = 7). FINDINGS: Median tissue-factor antigen and activity concentrations were significantly higher in plaques from patients with unstable angina and myocardial infarction than in those from patients with stable angina (antigen: 66.1 pg/mg [interquartile range 43.8-82.5] vs 32.4 pg/mg [9.8-43.4], p = 0.0001; activity: 0.22 mU/mg [0.17-0.41] vs 0.13 mU/mg [0.05-0.16], p = 0.0004). INTERPRETATION: Tissue-factor, an initiator of the coagulation cascade, may account for the different thrombotic responses to the rupture of human coronary atherosclerotic plaques. 相似文献