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排序方式: 共有916条查询结果,搜索用时 15 毫秒
11.
Rosario G. Garroppo Stefano Giordano Davide Iacono Luca Tavanti 《Wireless Networks》2011,17(6):1441-1459
In WiMAX systems the Base Station scheduler plays a key role as it controls the sharing of the radio resources among the users. The goal of the scheduler is multiple: achieve fair usage of the resources, satisfy the QoS requirements of the users, maximize goodput, and minimize power consumption, and at the same time ensuring feasible algorithm complexity and system scalability. Since most of these goals are contrasting, scheduler designers usually focus their attention on optimizing one aspect only. In this scenario, we propose a scheduling algorithm (called GTSNmathrm{GTS_N}) whose goal is to contemporaneously achieve efficiency and fairness, while also taking into account the QoS requirements and the channel state. GTSNmathrm{GTS_N} exploits the properties of Time Utility Functions (TUFs) and Game Theory. Simulations prove that the performance of GTSN,mathrm{GTS_N}, when compared to that of several well-known schedulers, is remarkable. GTSNmathrm{GTS_N} provides the best compromise between the two contrasting objectives of fairness and efficiency, while QoS requirements are in most cases guaranteed. However, the exponential complexity introduced by the game theory technique makes it rather impractical and not computationally scalable for a large number of users. Thus we developed a suboptimal version, named sub-GTSN.mathrm{GTS_N}. We show that this version retains most of the features and performance figures of its brother, but its complexity is linear with the number of users. 相似文献
12.
Investigating the chlorination of acidic pharmaceuticals and by-product formation aided by an experimental design methodology 总被引:1,自引:0,他引:1
José Benito Quintana Rosario Rodil Purificación López-Mahía Soledad Muniategui-Lorenzo 《Water research》2010,44(1):243-255
The degradation of seven acidic drugs and two metabolites during chlorination was investigated by liquid chromatography-mass spectrometry (LC-MS). A triple-quadrupole (QqQ) system was used to follow the time course of the pharmaceuticals and by-products, while a quadrupole time-of-flight (Q-TOF) system was also used for the identification of the by-products. Under strong chlorination conditions (10 mg/L Cl2, 24 h), only four of the target compounds were significantly degraded: salicylic acid, naproxen, diclofenac and indomethacine. The degradation kinetics of these four compounds were investigated at different concentrations of chlorine, bromide and pH by means of a Box-Behnken experimental design. Depending on these factors, measured pseudo-first order half-lives were in the ranges: 23-573 h for salicylic acid, 13-446 min for naproxen, 5-328 min for diclofenac and 0.4-13.4 min for indomethacine. Also, it was observed that chlorine concentration was the overall most significant factor, followed by the bromide concentration (except for indomethacine), resulting in increased degradation kinetics as they are increased. The degradation path of salicylic acid, naproxen and diclofenac consisted of aromatic substitution of one or two hydrogens by chlorine and/or bromide. Moreover, for diclofenac, two other by-products corresponding to a decarboxylation/hydroxylation pathway from the monohalogenated products were also identified. On the other hand, indomethacine degradation did not lead to halogenation products but to oxidation ones. The investigation of these by-products in real samples by LC-MS/MS (QqQ) showed that the halogenated derivates of salicylic acid occurred in all the drinking water and wastewater samples analysed. 相似文献
13.
Juan Carlos Fernndez-Martín Ana María Espinosa-Oliva Irene García-Domínguez Isaac Rosado-Snchez Yolanda M. Pacheco Rosario Moyano Jos G. Monterde Jos Luis Venero Rocío M. de Pablos 《International journal of molecular sciences》2022,23(3)
Lipopolysaccharide (LPS)-induced endotoxemia induces an acute systemic inflammatory response that mimics some important features of sepsis, the disease with the highest mortality rate worldwide. In this work, we have analyzed a murine model of endotoxemia based on a single intraperitoneal injection of 5 mg/kg of LPS. We took advantage of galectin-3 (Gal3) knockout mice and found that the absence of Gal3 decreased the mortality rate oflethal endotoxemia in the first 80 h after the administration of LPS, along with a reduction in the tissular damage in several organs measured by electron microscopy. Using flow cytometry, we demonstrated that, in control conditions, peripheral immune cells, especially monocytes, exhibited high levels of Gal3, which were early depleted in response to LPS injection, thus suggesting Gal3 release under endotoxemia conditions. However, serum levels of Gal3 early decreased in response to LPS challenge (1 h), an indication that Gal3 may be extravasated to peripheral organs. Indeed, analysis of Gal3 in peripheral organs revealed a robust up-regulation of Gal3 36 h after LPS injection. Taken together, these results demonstrate the important role that Gal3 could play in the development of systemic inflammation, a well-established feature of sepsis, thus opening new and promising therapeutic options for these harmful conditions. 相似文献
14.
de Oliveira Amanda Gerhardt Moreno Janaina Fernandes de Sousa Ana Maria Furtado Esccio Viviane Alves de Oliveira Cavalcanti Guimares Maria Jos da Silva Ana Lucia Nazareth 《Polymer Bulletin》2020,77(6):2889-2904
Polymer Bulletin - Investigating the compatibility mechanism of hybrid composites based on two polymers and one mineral nanofiller is a challenge that needs to be better understood. This study... 相似文献
15.
We examined a range of oenological lactic acid bacteria species and reference strains for their potential to degrade tannins. Bacterial tannase activity was checked by a spectrophotometric and a visual reading method. None of the strains belonging to the oenological species of the genus Lactobacillus, Leuconostoc, Oenococcus or Pediococcus were tannase producers, with the exception of Lactobacillus plantarum. All the L. plantarum strains analyzed were positive for tannase activity and their identities were reconfirmed by L. plantarum PCR-specific assay or by sequencing the 16S rDNA. Tannase activity could be considered an important criterion for the selection of malolactic starter cultures since it might confer advantages in the winemaking process by reducing astringency and haze in wine. 相似文献
16.
Tiziana Di Chiara Alessandro Del Cuore Mario Daidone Stefania Scaglione Rosario Luca Norrito Maria Grazia Puleo Rosario Scaglione Antonio Pinto Antonino Tuttolomondo 《International journal of molecular sciences》2022,23(5)
There is growing evidence that hypertension is the most important vascular risk factor for the development and progression of cardiovascular and cerebrovascular diseases. The brain is an early target of hypertension-induced organ damage and may manifest as stroke, subclinical cerebrovascular abnormalities and cognitive decline. The pathophysiological mechanisms of these harmful effects remain to be completely clarified. Hypertension is well known to alter the structure and function of cerebral blood vessels not only through its haemodynamics effects but also for its relationships with endothelial dysfunction, oxidative stress and inflammation. In the last several years, new possible mechanisms have been suggested to recognize the molecular basis of these pathological events. Accordingly, this review summarizes the factors involved in hypertension-induced brain complications, such as haemodynamic factors, endothelial dysfunction and oxidative stress, inflammation and intervention of innate immune system, with particular regard to the role of Toll-like receptors that have to be considered dominant components of the innate immune system. The complete definition of their prognostic role in the development and progression of hypertensive brain damage will be of great help in the identification of new markers of vascular damage and the implementation of innovative targeted therapeutic strategies. 相似文献
17.
Giuseppe Donato Mangano Malak Fouani Daniela DAmico Valentina Di Felice Rosario Barone 《International journal of molecular sciences》2022,23(6)
Cachexia is a multifactorial and multi-organ syndrome that is a major cause of morbidity and mortality in late-stage chronic diseases. The main clinical features of cancer-related cachexia are chronic inflammation, wasting of skeletal muscle and adipose tissue, insulin resistance, anorexia, and impaired myogenesis. A multimodal treatment has been suggested to approach the multifactorial genesis of cachexia. In this context, physical exercise has been found to have a general effect on maintaining homeostasis in a healthy life, involving multiple organs and their metabolism. The purpose of this review is to present the evidence for the relationship between inflammatory cytokines, skeletal muscle, and fat metabolism and the potential role of exercise training in breaking the vicious circle of this impaired tissue cross-talk. Due to the wide-ranging effects of exercise training, from the body to the behavior and cognition of the individual, it seems to be able to improve the quality of life in this syndrome. Therefore, studying the molecular effects of physical exercise could provide important information about the interactions between organs and the systemic mediators involved in the overall homeostasis of the body. 相似文献
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19.
Alvin B. Culaba Aaron Jules R. Del Rosario Aristotle T. Ubando Jo-Shu Chang 《国际能源研究杂志》2020,44(12):9646-9658
The rise of mixed-use buildings contributes to the sustainable development of cities but are still met with challenges in energy management due to the lack of energy efficiency and sustainability guidelines. The use of integrated renewable-storage energy systems is a more beneficial solution to this problem over individual solutions; however, most design studies only focused on single-type buildings. Thus, this study aims to optimally design an integrated energy system for mixed-use buildings using HOMER Grid. The objective is to minimize the net present costs, subject to capacity limits, energy balances, and operational constraints. Economic metrics were used to evaluate and compare the proposed system to the varying design cases such as business-as-usual, stand-alone renewable source, and stand-alone energy storage. The case study considered a mixed-use building in a tropical area, with a solar photovoltaic system as the renewable energy source and lithium-ion battery as the energy storage system technology. The results show that the integrated system is the most financially attractive design case. It has a levelized cost of electricity of 0.1384 US$ kWh−1, which is significantly less than the 0.2580 US$ kWh−1 baseline. The system also provides electricity cost savings of 294 698 US$ y−1, excess electricity of 35 746 kWh, and carbon emission reduction of 550 tons annually for a mixed-use building with daily average consumption of 4557-kWh and 763-kW peak demand. 相似文献
20.