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51.
Kreutzer Jeffrey S.; Harris-Marwitz Jennifer; Myers Stefanie L. 《Canadian Metallurgical Quarterly》1990,4(4):249
Provides information about issues confronting neuropsychologists involved in brain injury litigation. Neuropsychologists are often involved as experts in the litigation process because of their unique role in assessment and treatment of brain injury sequelae. Focus is on evaluation, preparation of reports, testimony, professional credibility, ethics, and responsibilities to the patient. Criteria for evaluating the expertise and credentials of psychologists hired by attorneys are presented. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
52.
Ali A. Moazzami Stefanie L. Haese Afaf Kamal‐Eldin 《European Journal of Lipid Science and Technology》2007,109(10):1022-1027
Sesame seed (Sesamum indicum L.) is a rich source of furofuran lignans with a wide range of potential biological activities. The major lignans in sesame seeds are the oil‐soluble sesamin and sesamolin, as well as glucosides of sesaminol and sesamolinol that reside in the defatted sesame flour. Upon refining of sesame oil, acid‐catalyzed transformation of sesamin to episesamin and of sesamolin to epimeric sesaminols takes place, making the profile of refined sesame oils different from that of virgin oils. In this study, the total lignan content of 14 sesame seeds ranged between 405 and 1178 mg/100 g and the total lignan content in 14 different products, including tahini, ranged between 11 and 763 mg/100 g. The content of sesamin and sesamolin in ten commercial virgin and roasted sesame oils was in the range of 444–1601 mg/100 g oil. In five refined sesame oils, sesamin ranged between 118 and 401 mg/100 g seed, episesamin between 12 and 206 mg/100 g seed, and the total contents of sesaminol epimers between 5 and 35 mg/100 g seed, and no sesamolin was found. Thus, there is a great variation in the types and amounts of lignans in sesame seeds, seed products and oils. This knowledge is important for nutritionists working on resolving the connection between diet and health. Since the consumption of sesame seed products is increasing steadily in Europe and USA, it is important to include sesame seed lignans in databases and studies pertinent to the nutritional significance of antioxidants and phytoestrogens. It is also important to differentiate between virgin, roasted and refined sesame oils. 相似文献
53.
The neural correlates of infant and adult goal prediction: Evidence for semantic processing systems.
Reid Vincent M.; Hoehl Stefanie; Grigutsch Maren; Groendahl Anna; Parise Eugenio; Striano Tricia 《Canadian Metallurgical Quarterly》2009,45(3):620
The sequential nature of action ensures that an individual can anticipate the conclusion of an observed action via the use of semantic rules. The semantic processing of language and action has been linked to the N400 component of the event-related potential (ERP). The authors developed an ERP paradigm in which infants and adults observed simple sequences of actions. In one condition the conclusion of the sequence was anticipated, whereas in the other condition the conclusion was not anticipated. Adults and infants at 9 months and 7 months were assessed via the same neural mechanisms—the N400 component and analysis of the theta frequency. Results indicated that adults and infants at 9 months produced N400-like responses when anticipating action conclusions. The infants at 7 months displayed no N400 component. Analysis of the theta frequency provided support for the relation between the N400 and semantic processing. This study suggests that infants at 9 months anticipate goals and use similar cognitive mechanisms to adults in this task. In addition, this result suggests that language processing may derive from understanding action in early development. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
54.
JP Horwitz I Massova TE Wiese BH Besler TH Corbett 《Canadian Metallurgical Quarterly》1994,37(6):781-786
The present study establishes correlations of in vivo growth inhibition of a solid tumor, pancreatic ductal adenocarcinoma (Panc03), of mice with the steric and electrostatic fields and the hydrophobic parameter log P of a series (32) of 1-[[2-(dialkylamino)alkyl]amino]- 9H-thioxanthen-9-ones by the 3D-QSAR method comparative molecular field analysis (CoMFA). The template molecular model was hycanthone methanesulfonate (19), the structure of which had been established previously by X-ray crystallography. The hycanthone base is protonated at the terminal nitrogen N(2), and an intramolecular hydrogen bond is present between the proximal nitrogen N(1) and carbonyl oxygen O(1) atoms. Crystallographic data also indicate a planar arrangement of bonds around N(1). However, the molecular geometry of 19, optimized by semiempirical molecular orbital methods (PM3, MNDO, AM1), showed the expected trigonal-pyramidal configuration for N(1). A comparison of MO and ab initio methods applied to a model compound, 1-amino-9H-thioxanthen-9-one, led to the selection of PM3 as the method for full geometry optimization of first the cationic and then the neutral forms of 1-32, whereas AM1 provided atomic charges for these same structures save those incorporating a sulfonamide moiety (5, 7, 20, 25, 26, 29, 31, and 32). Acceptable values for the latter were obtained from ab initio calculations. Structures were aligned by minimizing root-mean-square (rms) differences in the fitting of structures to 19 using the FIT option of SYBYL. An alternative strategy of alignment, steric and electrostatic alignment (SEAL), was invoked to provide a comparison of statistical data generated with the rms alignment. The rms-fit alignment of structures produced slightly better cross-validated and conventional r2 values than those generated with the SEAL method. In addition, the rms-fit data indicate that a shift in the lattice of one-half of its spacing has a much smaller effect on the CoMFA data for a lattice of 1 A than one of 2 A. Inclusion of log P in a CoMFA of the neutral structures effected a small (ca. 8-10%) but significant improvement in cross-validated r2 values. The relative contributions of the hydrophobic effects and the steric and electrostatic fields to the conventional r2 values were 16%, 42%, and 42%, respectively. By contrast, incorporation of frontier molecular orbital (HOMO and LUMO) energies or their gaps in the PLS analyses failed to enhance correlation coefficients derived for either the charged or uncharged compounds.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
55.
Franziska Hornung Julia Rogal Peter Loskill Bettina Lffler Stefanie Deinhardt-Emmer 《International journal of molecular sciences》2021,22(7)
Obesity is a globally increasing health problem, entailing diverse comorbidities such as infectious diseases. An obese weight status has marked effects on lung function that can be attributed to mechanical dysfunctions. Moreover, the alterations of adipocyte-derived signal mediators strongly influence the regulation of inflammation, resulting in chronic low-grade inflammation. Our review summarizes the known effects regarding pulmonary bacterial and viral infections. For this, we discuss model systems that allow mechanistic investigation of the interplay between obesity and lung infections. Overall, obesity gives rise to a higher susceptibility to infectious pathogens, but the pathogenetic process is not clearly defined. Whereas, viral infections often show a more severe course in obese patients, the same patients seem to have a survival benefit during bacterial infections. In particular, we summarize the main mechanical impairments in the pulmonary tract caused by obesity. Moreover, we outline the main secretory changes within the expanded adipose tissue mass, resulting in chronic low-grade inflammation. Finally, we connect these altered host factors to the influence of obesity on the development of lung infection by summarizing observations from clinical and experimental data. 相似文献
56.
Stefanie Dietmair Lars K. Nielsen Nicholas E. Timmins 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2011,86(7):905-914
Mammalian cells are the preferred host for the manufacture of a wide range of biopharmaceuticals, but production costs are high owing to low productivity. A range of rational engineering strategies have been pursued in order to increase volumetric product titres from mammalian cells, such as delaying apoptosis, manipulation of the cell cycle, and improving metabolism and protein processing. Unfortunately, outcomes from these strategies have been mixed, with few instances where significant improvements in product yield have been achieved. This article reviews and contrasts many of the engineering strategies attempted to date, highlighting the variability and context specificity in outcome. The paper argues that this is a reflection of the complexity of mammalian cells, and that a deeper understanding of the biology underpinning protein production for biotechnological purposes is required. Copyright © 2011 Society of Chemical Industry 相似文献
57.
58.
Determining good parameter estimates in (exponential smooth transition autoregressive) models is known to be difficult. We show that the phenomena of getting strongly biased estimators is a consequence of the so‐called identification problem, the problem of properly distinguishing the transition function in relation to extreme parameter combinations. This happens in particular for either very small or very large values of the error term variance. Furthermore, we introduce a new alternative model – the TSTAR model – which has similar properties as the ESTAR model but reduces the effects of the identification problem. We also derive a linearity and a unit root test for this model. 相似文献
59.
The mechanical and adhesion behavior of cationically polymerized, partially crystalline epoxy networks is presented. For this, a reactive and a nonreactive poly(?-caprolactone) (PCL) were used as the crystalline component for the formation of copolymers and polymer alloys, respectively. The trade-off between toughness on the one hand and glass transition temperature and mechanical strength on the other can be reduced by the presence of nanostructures in combination with small crystalline domains (1 μm), as in the case of epoxy/PCL-based polymer alloys. This structure–property relationship reveals that a certain degree of crystallinity leads to enhanced toughness in cationically polymerized epoxy networks. 相似文献
60.
Stefanie Hähnlein Nelson Molina-Giraldo Philipp Blum Peter Bayer Peter Grathwohl 《Grundwasser》2010,15(2):123-133
Shallow geothermal energy installations, especially ground source heat pump (GSHP) systems are increasingly being used for air conditioning and temperature control in buildings. Heating applications, for example, result in cold temperature anomalies (cold plumes) in the subsurface. To avoid interactions between adjacent cold plumes, authorities recommend minimum distances of about 10 m between installations. The length of these plumes can be simulated analytically and numerically. The presented analytical solutions are valid for steady-state conditions and consider conduction, convection and dispersion. The results show that the length depends on different parameters, especially flow velocity. The plumes in gravel aquifers become temporarily longer than in less permeable aquifers. Even under average energy extraction rates, they can exceed 10 m in length after one heating period. In the presented example the plume has a length of 10 m after 100 days under a continuous energy extraction rate of 55 W?m?1. However, these plumes can regenerate quickly. Finally, the analytical results are discussed in a legal context. 相似文献