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51.
Laura Dipasquale Giuliana d'Ippolito Carmela Gallo Filomena Monica Vella Agata Gambacorta Gianluca Picariello Angelo Fontana 《International Journal of Hydrogen Energy》2012
Planktic diatoms are the largest primary producers in marine and freshwater habitats. Their dry biomass accumulates up to 50% of lipids and contains water-soluble β-1,3-glucans as major storage products. Because of the world-wide abundance of these photosynthetic protists, β-1,3-glucans may rival cellulose as the polysaccharide with the highest annual production on Earth. Here we show the feasibility of a simple and efficient process leading to bio-hydrogen by dark fermentation of microalgal biomass with the thermophilic bacterium Thermotoga neapolitana. Production of the biogas on minimum medium supplemented only with the extract of the diatom Thalassiosira weissflogii proved that algal biomass per se can serve as substrate for sustaining the biotechnological process with no requirement of any pretreatment and external integration of other nutrients. At the same time, lipids unused for the anaerobic production of the biogas, can be employed for production of bio-diesel, thus considerably increasing the economic potential of these renewable feedstocks. 相似文献
52.
Santangelo S Lanza M Piperopoulos E Milone C 《Journal of nanoscience and nanotechnology》2012,12(3):2424-2436
Taguchi's robust design method is for the first time employed to optimize many aspects of the production of nanohybrids based on C nanotubes by iron-catalyzed chemical vapor deposition in i-C4H10 + H2 atmosphere. By analyzing the outcomes of the catalytic process in terms of selectivity, carbon yield, purity and crystalline arrangement of the hybrid-forming nanotubes, the influence is ranked of the following parameters: synthesis temperature (500-700 degrees C), support material (alumina, magnesia or sodium-exchanged montmorillonite), calcination- (450-750 degrees C) and reduction-(500-700 degrees C) temperatures of the 15 wt% Fe-catalyst. In the experiments initially performed for this purpose, the growth process had, on average, scarce selectivity (2 in a scale 1-5) and poor yield (130 wt%); carbonaceous deposits exhibited unsatisfactory graphitization degree (Raman D/G intensity ratio > 1.5) and contained large amounts of metal impurities (14 wt%) and amorphous carbon (5 wt%). The indications emerging from Taguchi approach to the process optimization are critically examined. The experimental conditions chosen for carrying out test experiments allow achieving excellent selectivity (5) or large yield (760 wt%), hybrids with well-graphitized nanotubes (D/G intensity ratio < 0.6), nearly free of metallic (0.3 wt%) or amorphous (0.4 wt%) inclusions, with consequent possibility of satisfying the different requisites that the specific application to be addressed may require. 相似文献
53.
In this paper the development of a new laboratory prototype for the emulation of a photovoltaic (PV) field is presented. The proposed system is based on a DC/DC step-down converter topology and allows to obtain the solar array I–V curves, taking into account the environmental changes in solar irradiance and cell temperature. The DC/DC converter control strategy is deduced by using a comprehensive mathematical model of the PV field whose parameters are obtained from the knowledge of: (a) maximum power point data, measured when the PV plant power converter is running, (b) open circuit voltage and short-circuit current, measured off-line. This approach allows the most accurate representation of the PV source. Computer simulations and experimental results demonstrate that the proposed circuit acts as a highly accurate and efficient laboratory simulator of the photovoltaic array electrical characteristics both in steady state and transient conditions. Partial shading and fluctuating conditions can be reproduced too. Moreover the dynamic behaviour of the proposed laboratory emulator is suitable to its effective connection to power electronic interface to the utility or to load through a DC/DC boost converter. 相似文献
54.
55.
Antonietta Baiano Carmela Scrocco Grazia Sepielli 《Critical reviews in food science and nutrition》2016,56(14):2391-2407
Wine is one of the most popular alcoholic beverages in the world, although it is mainly consumed in European and South American countries. Several thousand years have passed since the product of grape fermentation was accidentally discovered. Over the last 100–150 years, winemaking has been completely revolutionized in terms of procedures and equipment. This work is aimed to give a comprehensive overview of the consolidated use of winemaking innovations that are still in the development stage or already applied to commercial products. Their effects on physical, chemical, and sensory characteristics of wines will also be discussed in comparison with the consolidated vinification procedures. 相似文献
56.
The acoustic emission technique is a very promising non-destructive and online capable approach for the detection of damage events in metal forming processes. The feasibility of using this testing method for online monitoring of cold forging processes of the case hardening steel 1.7321 (20MoCr4) was experimentally proven. In this paper, exemplary upsetting tests under varying test conditions were continuously monitored to analyze the relationship between cracking and resulting AE as well as to determine ideal AE measuring parameters. Finally, the critical forming stage of an industrial cold forging process for manufacturing of drive bevel gears is examined by applying acoustic emission technique. Cracking and tool wear were detected by analyzing the distribution of the AE parameters energy, hits and amplitude over the forming process. 相似文献
57.
Massimo D'Archivio Carmela Santangelo Beatrice Scazzocchio Rosaria Var�� Carmela Filesi Roberta Masella Claudio Giovannini 《International journal of molecular sciences》2008,9(3):213-228
Polyphenols, occurring in fruit and vegetables, wine, tea, extra virgin olive oil, chocolate and other cocoa products, have been demonstrated to have clear antioxidant properties in vitro, and many of their biological actions have been attributed to their intrinsic reducing capabilities. However, it has become clear that, in complex biological systems, polyphenols exhibit several additional properties which are yet poorly understood. Apoptosis is a genetically controlled and evolutionarily conserved form of cell death of critical importance for the normal embryonic development and for the maintenance of tissue homeostasis in the adult organism. The malfunction of the death machinery may play a primary role in various pathological processes, since too little or too much apoptosis can lead to proliferative or degenerative diseases, respectively. Cancer cells are characterized by a deregulated proliferation, and/or an inability to undergo programmed cell death. A large body of evidence indicates that polyphenols can exert chemopreventive effects towards different organ specific cancers, affecting the overall process of carcinogenesis by several mechanisms: inhibition of DNA synthesis, modulation of ROS production, regulation of cell cycle arrest, modulation of survival/proliferation pathways. In addition, polyphenols can directly influence different points of the apoptotic process, and/or the expression of regulatory proteins. Although the bulk of data has been obtained in in vitro systems, a number of clinical studies suggesting a preventive and therapeutic effectiveness of polyphenols in vivo is available. However, a deeper knowledge of the underlying mechanisms responsible for the modulation of apoptosis by polyphenols, and their real effectiveness, is necessary in order to propose them as potential chemopreventive and chemotherapeutic candidates for cancer treatment. 相似文献
58.
Four molecular Pt-carbonyl clusters decorated by Cd-Br fragments, i.e., [Pt(13)(CO)(12){Cd(5)(μ-Br)(5)Br(2)(dmf)(3)}(2)](2-) (1), [Pt(19)(CO)(17){Cd(5)(μ-Br)(5)Br(3)(Me(2)CO)(2)}{Cd(5)(μ-Br)(5)Br(Me(2)CO)(4)}](2-) (2), [H(2)Pt(26)(CO)(20)(CdBr)(12)](8-) (3) and [H(4)Pt(26)(CO)(20)(CdBr)(12)(PtBr)(x)](6-) (4) (x = 0-2), have been obtained from the reactions between [Pt(3n)(CO)(6n)](2-) (n = 2-6) and CdBr(2)·H(2)O in dmf at 120 °C. The structures of these molecular clusters with diameters of 1.5-2 nm have been determined by X-ray crystallography. Both 1 and 2 are composed of icosahedral or bis-icosahedral Pt-CO cores decorated on the surface by Cd-Br motifs, whereas 3 and 4 display a cubic close packed Pt(26)Cd(12) metal frame decorated by CO and Br ligands. An oversimplified and unifying approach to interpret the electron count of these surface decorated platinum carbonyl clusters is suggested, and extended to other low-valent organometallic clusters and Au-thiolate nanoclusters. 相似文献
59.
Dantas-Barbosa C de Macedo Brigido M Maranhao AQ 《International journal of molecular sciences》2012,13(5):5420-5440
Since the advent of phage display technology, dating back to 1985, antibody libraries displayed on filamentous phage surfaces have been used to identify specific binders for many different purposes, including the recognition of tumors. Phage display represents a high-throughput technique for screening billions of random fusion antibodies against virtually any target on the surface or inside cancer cells, or even soluble markers found in patient serum. Many phage display derived binders targeting important tumor markers have been identified. Selection directed to tumoral cells' surfaces lead to the identification of unknown tumoral markers. Also the improvement of methods that require smaller amounts of cells has opened the possibility to use this approach on patient samples. Robust techniques combining an antibody library displayed on the phage surface and protein microarray allowed the identification of auto antibodies recognized by patient sera. Many Ab molecules directly or indirectly targeting angiogenesis have been identified, and one of them, ramucirumab, has been tested in 27 phase I-III clinical trials in a broad array of cancers. Examples of such antibodies will be discussed here with emphasis on those used as probes for molecular imaging and other clinical trials. 相似文献
60.
NA Lokman AS Elder C Ricciardelli MK Oehler 《International journal of molecular sciences》2012,13(8):9959-9970
The majority of ovarian cancer patients present with advanced disease and despite aggressive treatment, prognosis remains poor. Significant improvement in ovarian cancer survival will require the development of more effective molecularly targeted therapeutics. Commonly, mouse models are used for the in vivo assessment of potential new therapeutic targets in ovarian cancer. However, animal models are costly and time consuming. Other models, such as the chick embryo chorioallantoic membrane (CAM) assay, are therefore an attractive alternative. CAM assays have been widely used to study angiogenesis and tumor invasion of colorectal, prostate and brain cancers. However, there have been limited studies that have used CAM assays to assess ovarian cancer invasion and metastasis. We have therefore developed a CAM assay protocol to monitor the metastatic properties of ovarian cancer cells (OVCAR-3, SKOV-3 and OV-90) and to study the effect of potential therapeutic molecules in vivo. The results from the CAM assay are consistent with cancer cell motility and invasion observed in in vitro assays. Our results demonstrate that the CAM assay is a robust and cost effective model to study ovarian cancer cell metastasis. It is therefore a very useful in vivo model for screening of potential novel therapeutics. 相似文献