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101.
Examined the ability of D. Stock and H. Thelen's (see pa, vol. 33:1008) measure of reactions to group situations (the reactions to group situations test) to provide a trainability index for screening potential t-group members. Trainability indexes were calculated, and self-disclosures and empathy ratings (mmpi role play scale) were measured previous to and following sensitivity training of 2 groups: (a) 12 negro psychiatric aide trainees, and (b) 6 caucasian and 3 negro office of economic opportunity aides. Positive relationships were found between trainability and the 2 t-group outcome measures (openness and empathy) for both groups. Results provide further validation for the trainability index in human service professions. (24 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
102.
Heavily compensated GaSb (2-in.-diameter substrates) with resistivity as high as 7 × 103 Ω-cm, corresponding to a net donor concentration of 3.5×1013 cm−3 at 77 K, and 16.4 Ω-cm, corresponding to net donor concentration of 1.16×1016 cm−3 at 300 K, have been obtained by tellurium (Te) compensation in vertical-Bridgman-grown bulk crystals. Very interesting p-
to n-type as well as n- to p-type changes have been observed as a function of temperature in these samples. 相似文献
103.
This paper describes the design and validation of a mathematical model for a solar Fresnel collector. The function of the model is to simulate the optical and thermal dynamics of a Fresnel system for heating water. The model is validated using real data gathered from a cooling plant with double effect absorption chiller located in the School of Engineering University of Seville, Spain (Experimental cooling plant is also described in the paper). Comparison of calculated and plant measured data shows that the error is lower than 3% in the optical model and within 7% in the thermal model.The model uses a new approach to include a solar tracking mirror mechanism in one axis. This tracking has been designed to maximise the reception of available solar radiation by the absorption pipe. The thermal model used is based around classical models for solar receivers and it is validated with real operating data gathered from a supervisor system.The Fresnel model has been designed with sufficient flexibility to consider different geometries and thermal parameters, and may be used to simulate the performance of a proposed Fresnel collector system at any location. 相似文献
104.
An organogelator with two distinct π-functional units is able to incorporate carbon nanotubes into its mesh of fibres in the gel state. The morphology of the material derived from this nanocomposite after evaporation of the solvent is a complex mesh of fibres which is clearly different from the pure gelator. This feature indicates a role of the nanotubes in assisting the formation of a fibre structure in the gel thanks to their interaction with the pyrene units in the organogelator. The nanocomposite conducts electricity once the p-type gelator is doped with iodine vapour. The change in morphology caused by the carbon material increases the conductivity of the material compared with the purely organic conducting system. It is remarkable that this improvement in the physical property is caused by an extremely small proportion of the carbon material (only present at a ratio of 0.1% w/w). The practically unique properties of TTF unit allow measurements with both doped and undoped materials with conducting atomic force microscopy which have demonstrated that the carbon nanotubes are not directly responsible for the increased conductivity. 相似文献
105.
Paride Salvatore Occhipinti Nunziatina Russo Paola Foti Irene Maria Zingale Alessandra Pino Flora Valeria Romeo Cinzia L. Randazzo Cinzia Caggia 《Journal of the science of food and agriculture》2024,104(7):3823-3833
The intensified attention to health, the growth of an elderly population, the changing lifestyles, and the medical discoveries have increased demand for natural and nutrient-rich foods, shaping the popularity of microalgae products. Microalgae thanks to their metabolic versatility represent a promising solution for a ‘green’ economy, exploiting non-arable land, non-potable water, capturing carbon dioxide (CO2) and solar energy. The interest in microalgae is justified by their high content of bioactive molecules, such as amino acids, peptides, proteins, carbohydrates, polysaccharides, polyunsaturated fatty acids (as ω-3 fatty acids), pigments (as β-carotene, astaxanthin, fucoxanthin, phycocyanin, zeaxanthin and lutein), or mineral elements. Such molecules are of interest for human and animal nutrition, cosmetic and biofuel production, for which microalgae are potential renewable sources. Microalgae, also, represent effective biological systems for treating a variety of wastewaters and can be used as a CO2 mitigation approach, helping to combat greenhouse gases and global warming emergencies. Recently a growing interest has focused on extremophilic microalgae species, which are easier to cultivate axenically and represent good candidates for open pond cultivation. In some cases, the cultivation and/or harvesting systems are still immature, but novel techniques appear as promising solutions to overcome such barriers. This review provides an overview on the actual microalgae cultivation systems and the current state of their biotechnological applications to obtain high value compounds or ingredients. Moreover, potential and future research opportunities for environment, human and animal benefits are pointed out. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献
106.
Srinu Tumpara Anna R. Gründing Kokilavani Sivaraman Sabine Wrenger Beata Olejnicka Tobias Welte Maria J. Wurm Paco Pino Divor Kiseljak Florian M. Wurm Sabina Janciauskiene 《International journal of molecular sciences》2021,22(15)
For the treatment of severe COVID-19, supplementation with human plasma-purified α-1 antitrypsin (AAT) to patients is currently considered. AAT inhibits host proteases that facilitate viral entry and possesses broad anti-inflammatory and immunomodulatory activities. Researchers have demonstrated that an interaction between SARS-CoV-2 spike protein (S) and lipopolysaccharides (LPS) enhances pro-inflammatory responses in vitro and in vivo. Hence, we wanted to understand the potential anti-inflammatory activities of plasma-derived and recombinant AAT (recAAT) in a model of human total peripheral blood mononuclear cells (PBMCs) exposed to a combination of CHO expressed trimeric spike protein and LPS, ex vivo. We confirmed that cytokine production was enhanced in PBMCs within six hours when low levels of LPS were combined with purified spike proteins (“spike”). In the presence of 0.5 mg/mL recAAT, however, LPS/spike-induced TNF-α and IL-1β mRNA expression and protein release were significantly inhibited (by about 46–50%) relative to LPS/spike alone. Although without statistical significance, recAAT also reduced production of IL-6 and IL-8. Notably, under the same experimental conditions, the plasma-derived AAT preparation Respreeza (used in native and oxidized forms) did not show significant effects. Our findings imply that an early pro-inflammatory activation of human PBMCs is better controlled by the recombinant version of AAT than the human plasma-derived AAT used here. Considering the increasing clinical interest in AAT therapy as useful to ameliorate the hyper-inflammation seen during COVID-19 infection, different AAT preparations require careful evaluation. 相似文献
107.
Maite Sanz Alaejos Vernica Pino Ana M. Afonso 《Food research international (Ottawa, Ont.)》2008,41(4):327-340
There is not sufficient scientific evidence to support the hypothesis that human cancer risk is specifically due to the intake of heterocyclic aromatic amines (HAAs) in diet. Epidemiological evidence appears to imply two main factors in the HAAs carcinogenicity. These factors are the very high frequency of consumption of red meats, and very darkly browned meats from cooking, which are HAAs-containing foods. The present review focuses on the fact that the cancer risk is notably enhanced when certain genotypes related to HAAs metabolism are present. Thus, genetic predisposition seems to be the main factor in cancer development related to HAAs, and possibly the co-presence of other mutagenic compounds in diet. 相似文献
108.
A common method of dynamically scheduling jobs in Flexible Manufacturing Systems (FMSs) is to employ dispatching rules. However, the problem associated with this method is that the performance of the rules depends on the state of the system, but there is no rule that is superior to all the others for all the possible states the system might be in. It would therefore be highly desirable to employ the most suitable rule for each particular situation. To achieve this, this paper presents a scheduling approach that uses Case-Based Reasoning (CBR), which analyzes the system's previous performance and acquires "scheduling knowledge," which determines the most suitable dispatching rule at each particular moment in time. Simulation results indicate that the proposed approach produces significant performance improvements over existing dispatching rules. 相似文献
109.
Rodriguez Pino M. Landesa L. Rodriguez J.L. Obelleiro F. Burkholder R.J. 《Antennas and Propagation, IEEE Transactions on》1999,47(6):961-969
In Holliday et al. (1995, 1996), the iterative forward-backward (FB) method has been proposed to solve the magnetic field integral equation (MFIE) for smooth one-dimensional (1-D) rough surfaces. This method has proved to be very efficient, converging in a very small number of iterations. Nevertheless, this solution becomes unstable when some obstacle, like a ship or a large breaking wave, is included in the original problem. In this paper, we propose a new method: the generalized forward-backward (GFB) method to solve such kinds of complex problems. The approach is formulated for the electric field integral equation (EFIE), which is solved using a hybrid combination of the conventional FB method and the method of moments (MoM), the latter of which is only applied over a small region around the obstacle. The GFB method is shown to provide accurate results while maintaining the efficiency and fast convergence of the conventional FB method. Some numerical results demonstrate the efficiency and accuracy of the new method even for low-grazing angle scattering problems 相似文献
110.
Miguel ngel Gonzlez-Moles Carmen Keim-del Pino Pablo Ramos-García 《International journal of molecular sciences》2022,23(21)
Oral lichen planus (OLP) is a common chronic inflammatory disease of unknown etiology and likely autoimmune nature that is currently considered an oral potentially malignant disorder, implying that patients suffering from this process are at risk of developing oral cancer in their lifetime. The molecular alterations that develop in OLP and that make the affected oral epithelium predisposed to malignancy are unknown, although, as in other autoimmune diseases (ulcerative colitis, primary biliary cirrhosis, etc.), they may be linked to oncogenesis-promoting effects mediated by the inflammatory infiltrate. So far there is no in-depth knowledge on how these hallmarks of cancer are established in the cells of the oral epithelium affected by OLP. In this scoping review of systematic reviews and meta-analyses the state of evidence based knowledge in this field is presented, to point out gaps of evidence and to indicate future lines of research. MEDLINE, Embase, Cochrane Library and Dare were searched for secondary-level studies published before October 2022. The results identified 20 systematic reviews and meta-analyses critically appraising the hallmarks tumor-promoting inflammation (n = 17, 85%), sustaining proliferative signaling (n = 2, 10%), and evading growth suppressors (n = 1, 5%). No evidence was found for the other hallmarks of cancer in OLP. In conclusion, OLP malignization hypothetically derives from the aggressions of the inflammatory infiltrate and a particular type of epithelial response based on increased epithelial proliferation, evasion of growth-suppressive signals and lack of apoptosis. Future evidence-based research is required to support this hypothesis. 相似文献