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排序方式: 共有344条查询结果,搜索用时 15 毫秒
61.
Laszlo Barna Iantovics Laszlo Kovacs Gyula Laszlo Fekete 《New Review of Information Networking》2016,21(2):101-116
An integrated library information system is a resource planning system for a library, used to track resources owned, bills paid, orders made, and patrons who have borrowed. In our research, we focused on university library information systems (ULISs). We identified an important research question regarding their main limitation in offering intelligent help to the students in their documentation/learning. We identified the importance of the endowment of ULISs with artificial intelligence. In this article, we analyzed different aspects related to the presence of computational intelligence in ULISs and intelligence of ULISs. Finally, we proposed a complex next generation ULIS based on a hybrid cooperative learning, being able to offer an intelligent help for personalized learning of students. We defined some novel paradigms in the context of a novel kind of cooperative hybrid personalized learning, such as learning role and sub-role; and learning intelligence level. 相似文献
62.
The fatty acid compositions of the blubber and melon oils from the beluga whale (Delphinapterus leucas) have been determined by gas liquid chromatography (GLC). The melon oil contains a high level (60.1 mole %) of isovaleric
acid, substantial amounts of long chain branched acids (16.9%), and very little polyunsaturated material (0.5%). The blubber
oil contains less isovaleric (13.2%), fewer long chain branched acids (2.7%), and appreciable amounts (10.9%) of the polyunsaturated
acids typical of marine oils. The blubber and melon oils were also examined for lipid class composition by thin layer chromatography
on silicic acid, direct GLC of the hydrogenated oil, and gel permeation chromatography. Both oils are composed almost entirely
of triglycerides, which can be separated chromatographically into molecules containing 0, 1 and 2 isovaleric acid moieties.
No triisovalerin could be detected. The blubber oil contains 68.9 mole % normal triacyl-, 24.2% diacyl-monoisovaleroyl-, and
7.0% monoacyl-diisovaleroyl-triglycerides (acyl=long chain acid). Monoacyl-diisovalerin constitutes 86.7 mole % of the melon
oil. This unusual compound may play a role in the echolocation system of the beluga whale. 相似文献
63.
Tibor S. Laszlo 《Solar Energy》1961,5(4):133-137
The mechanism of heating solids with radiant energy is reviewed and the need for measuring radiative properties is pointed out. Image furnaces are suitable for such measurement at high temperatures. The limitations of image furnace operations are discussed and methods as well as equipment offered to overcome the limitations. The importance of artificial black bodies in high-flux measurements is described and a new shape for such cavities is proposed. Data comparing this shape with hitherto used shapes are tabulated. Design for a fast-action on-off shutter for image furnaces is presented. In its retracted position the shutter does not cast any shadow on the mirror and it does not require artificial cooling even when exposed to radiation. 相似文献
64.
Salt rejection and ion selectivity of NF-255 and NF-45 nanofiltration (NF) membranes were investigated. The rejection of two cations (Na+, Ca2+) and two anions (Cl−, SO42−) which are common in natural and in industrial wastewater, were studied as a function of pH at permanent pressure and temperature. The ion rejection of NF membranes were investigated in single salt solutions like NaCl, CaCl2, Na2SO4, CaSO4, and in multicomponent systems that contained all the previous ions. We found that, there is a minimum rejection of the Na+ and Cl− ions between pH 4-5 in NF-255 and between pH 7-8 in NF-45. The rejection of calcium ions were increased in each case at lower pH in both membranes. However the pH value where the ion rejection behaviour of membranes changed, were different: pH 4 in NF-255 and pH 8 in NF-45. In NF-45 the chloride ion has negative rejection which depends on the quality of ions and the pH. We found that below pH values of 4 the selectivity of mono- and multivalent cations considerable increased in NF-255. This phenomena may be used for separation of calcium ions from sodium ions from weakly acidic (hydrochloric and sulfuric acid) solution, e.g. regeneration solution of sodium form softening ion exchangers. 相似文献
65.
Joseph A. Laszlo Steven C. Cermak Kervin O. Evans David L. Compton Roque Evangelista Mark A. Berhow 《European Journal of Lipid Science and Technology》2013,115(3):363-371
Effective lipophilic antioxidants were prepared by non‐aqueous enzymatic transesterification of plant phenols with cuphea oil. Tyrosol and hydroxytyrosol, abundantly available phenols from olive oil processing byproduct, were found to be predominately acylated with capric acid derived from the triglyceride fraction of the Cuphea germplasm line PSR 23 (Cuphea Viscosissima × C. lanceolata). The reaction was complete within 2 h, with a >97% conversion of either phenol using immobilized Candida antarctica lipase B. The reaction products were good solvents for tyrosol or hydroxytyrosol, suggesting a facile manufacturing route not dependent on use of organic solvents. Phenolic derivatives were assessed for their ability to serve as antioxidants for preventing the oxidation of polyunsaturated fatty acyl groups. The antioxidant capacities of the cuphea‐derived fatty acyl derivatives of tyrosol or hydroxytyrosol were the same as their respective derivatives prepared from decanoic acid. These biobased antioxidants may improve the oxidative stability of sensitive fatty acids in food applications. Practical applications: A new biobased antioxidant was created for the food industry. Foods can contain fats and oils that are susceptible to deterioration during storage, which can limit product quality and shelf‐life. Synthetic antioxidants can slow the spoilage process, although there are limitations to how much can be added to foods. The food industry is interested in using natural ingredients to solve storage stability problems. We found that the oil from the plant Cuphea, cultivated in the upper Midwest region of the US, is very useful for modifying olive oil waste molecules to create antioxidants for use in foods. The developed process would be suitable for commercial production. This research creates a new commercial use for a specialty oil seed crop, expands the market for cuphea oil, and has developed two novel antioxidants to help the food industry improve food quality. 相似文献
66.
Fabian G Farago N Feher LZ Nagy LI Kulin S Kitajka K Bito T Tubak V Katona RL Tiszlavicz L Puskas LG 《International journal of molecular sciences》2011,12(9):6116-6134
Toxicogenomics, based on the temporal effects of drugs on gene expression, is able to predict toxic effects earlier than traditional technologies by analyzing changes in genomic biomarkers that could precede subsequent protein translation and initiation of histological organ damage. In the present study our objective was to extend in vivo toxicogenomic screening from analyzing one or a few tissues to multiple organs, including heart, kidney, brain, liver and spleen. Nanocapillary quantitative real-time PCR (QRT-PCR) was used in the study, due to its higher throughput, sensitivity and reproducibility, and larger dynamic range compared to DNA microarray technologies. Based on previous data, 56 gene markers were selected coding for proteins with different functions, such as proteins for acute phase response, inflammation, oxidative stress, metabolic processes, heat-shock response, cell cycle/apoptosis regulation and enzymes which are involved in detoxification. Some of the marker genes are specific to certain organs, and some of them are general indicators of toxicity in multiple organs. Utility of the nanocapillary QRT-PCR platform was demonstrated by screening different references, as well as discovery of drug-like compounds for their gene expression profiles in different organs of treated mice in an acute experiment. For each compound, 896 QRT-PCR were done: four organs were used from each of the treated four animals to monitor the relative expression of 56 genes. Based on expression data of the discovery gene set of toxicology biomarkers the cardio- and nephrotoxicity of doxorubicin and sulfasalazin, the hepato- and nephrotoxicity of rotenone, dihydrocoumarin and aniline, and the liver toxicity of 2,4-diaminotoluene could be confirmed. The acute heart and kidney toxicity of the active metabolite SN-38 from its less toxic prodrug, irinotecan could be differentiated, and two novel gene markers for hormone replacement therapy were identified, namely fabp4 and pparg, which were down-regulated by estradiol treatment. 相似文献
67.
68.
Laszlo G. Harsing Jr. Gbor Sznsi Tibor Zelles Lszl Kles 《International journal of molecular sciences》2021,22(12)
Neurodegenerative–neuroinflammatory disorders of the retina seriously hamper human vision. In searching for key factors that contribute to the development of these pathologies, we considered potential interactions among purinergic neuromodulation, glycinergic neurotransmission, and microglia activity in the retina. Energy deprivation at cellular levels is mainly due to impaired blood circulation leading to increased release of ATP and adenosine as well as glutamate and glycine. Interactions between these modulators and neurotransmitters are manifold. First, P2Y purinoceptor agonists facilitate reuptake of glycine by glycine transporter 1, while its inhibitors reduce reverse-mode operation; these events may lower extracellular glycine levels. The consequential changes in extracellular glycine concentration can lead to parallel changes in the activity of NR1/NR2B type NMDA receptors of which glycine is a mandatory agonist, and thereby may reduce neurodegenerative events in the retina. Second, P2Y purinoceptor agonists and glycine transporter 1 inhibitors may indirectly inhibit microglia activity by decreasing neuronal or glial glycine release in energy-compromised retina. These inhibitions may have a role in microglia activation, which is present during development and progression of neurodegenerative disorders such as glaucomatous and diabetic retinopathies and age-related macular degeneration or loss of retinal neurons caused by thromboembolic events. We have hypothesized that glycine transporter 1 inhibitors and P2Y purinoceptor agonists may have therapeutic importance in neurodegenerative–neuroinflammatory disorders of the retina by decreasing NR1/NR2B NMDA receptor activity and production and release of a series of proinflammatory cytokines from microglial cells. 相似文献
69.
Laszlo J. Kecskes 《Metallurgical and Materials Transactions A》1999,30(9):2483-2489
The hot explosive compaction (HEC) technique developed for tungsten-titanium (W-Ti) alloys has been applied to molybdenum-titanium
(Mo-Ti) alloys as well. The Mo+Ti powders were mixed and surrounded by an exothermic Ti+C mixture. The TiC reaction, when
ignited, released a large amount of heat via a self-propagating high-temperature synthesis (SHS) reaction. Heat from the SHS reaction diffused into the Mo+Ti powder bed,
causing the interior temperature to rise above 1500 °C. When the powder bed became isothermal, it was consolidated to high
density by pressure waves generated by the detonation of an explosive. The amount of explosive charge and the molar ratio
of exothermic mixture to sample were adjusted to produce full-density Mo-Ti alloy billets. The billets were sectioned and
examined with scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction analysis (XRD),
and microhardness measurements. In the context of the original fabrication process, the evolution of the resultant microstructure
of the Mo-Ti product is described. 相似文献
70.