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101.
Rebecca Wall R. Paul Ross Fergus Shanahan Liam O’Mahony Barry Kiely Eamonn Quigley Timothy G. Dinan Gerald Fitzgerald Catherine Stanton 《Lipids》2010,45(5):429-436
Recently, we reported that administration of Bifidobacteria resulted in increased concentrations of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in murine adipose tissue
[1]. The objective of this study was to assess the impact of co-administration of Bifidobacterium breve NCIMB 702258 and the substrate for EPA, α-linolenic acid, on host fatty acid composition. α-Linolenic acid-supplemented diets
(1%, wt/wt) were fed to mice (n = 8), with or without B. breve NCIMB 702258 (daily dose of 109 microorganisms) for 8 weeks. Two further groups received either supplement of B. breve alone or unsupplemented diet. Tissue fatty acid composition was assessed by gas liquid chromatography. Dietary supplementation
of α-linolenic acid resulted in higher (P < 0.05) α-linolenic acid and EPA concentrations in liver and adipose tissue and lower (P < 0.05) arachidonic acid in liver, adipose tissue and brain compared with mice that did not receive α-linolenic acid. Supplementation
with B. breve NCIMB 702258 in combination with α-linolenic acid resulted in elevated (P < 0.05) liver EPA concentrations compared with α-linolenic acid supplementation alone. Furthermore, the former group had
higher (P < 0.05) DHA in brain compared with the latter group. These results suggest a role for interactions between fatty acids and
commensals in the gastrointestinal tract. This interaction between administered microbes and fatty acids could result in a
highly effective nutritional approach to the therapy of a variety of inflammatory and neurodegenerative conditions. 相似文献
102.
Jonathan M. Stephens Ralf C. Schlothauer Bruce D. Morris Derek Yang Liam Fearnley David R. Greenwood Kerry M. Loomes 《Food chemistry》2010
The principal phenolic compounds and methylglyoxal were analysed in New Zealand Leptospermum scoparium (manuka) and Kunzea ericoides (kanuka) honeys. These honeys shared six phenolic acids as primary components and differentiation was possible as relative proportions varied. Manuka honey contained an elevated concentration of a trimethoxybenzoic acid and methylglyoxal; and 2-methoxybenzoic acid and methylglyoxal concentrations were linearly correlated in fresh manuka honey. Kanuka honey contained an elevated concentration of methoxyphenyllactic acid. The concentration of the phenolic components increased with maturation in both honey types; and this profile development, along with a corresponding increase of methylglyoxal concentration, was linear in manuka honey. Nectar analysed from the plant species contained the same phenolic components as the honeys. These results demonstrated the phenolic profile could be used to differentiate the honey types, heat treatment of honey could be identified, and the presence of these components may contribute to the efficacy of these honeys in therapeutic uses. 相似文献
103.
T. L. Youd I. M. Idriss Ronald D. Andrus Ignacio Arango Gonzalo Castro John T. Christian Richardo Dobry W. D. Liam Finn Leslie F. Harder Jr. Mary Ellen Hynes Kenji Ishihara Joseph P. Koester Sam S. C. Liao William F. Marcuson III Geoffrey R. Martin James K. Mitchell Yoshiharu Moriwaki Maurice S. Power Peter K. Robertson Raymond B. Seed Kenneth H. Stokoe II 《Canadian Metallurgical Quarterly》2001,127(10):817-833
Following disastrous earthquakes in Alaska and in Niigata, Japan in 1964, Professors H. B. Seed and I. M. Idriss developed and published a methodology termed the “simplified procedure” for evaluating liquefaction resistance of soils. This procedure has become a standard of practice throughout North America and much of the world. The methodology which is largely empirical, has evolved over years, primarily through summary papers by H. B. Seed and his colleagues. No general review or update of the procedure has occurred, however, since 1985, the time of the last major paper by Professor Seed and a report from a National Research Council workshop on liquefaction of soils. In 1996 a workshop sponsored by the National Center for Earthquake Engineering Research (NCEER) was convened by Professors T. L. Youd and I. M. Idriss with 20 experts to review developments over the previous 10 years. The purpose was to gain consensus on updates and augmentations to the simplified procedure. The following topics were reviewed and recommendations developed: (1) criteria based on standard penetration tests; (2) criteria based on cone penetration tests; (3) criteria based on shear-wave velocity measurements; (4) use of the Becker penetration test for gravelly soil; (4) magnitude scaling factors; (5) correction factors for overburden pressures and sloping ground; and (6) input values for earthquake magnitude and peak acceleration. Probabilistic and seismic energy analyses were reviewed but no recommendations were formulated. 相似文献
104.
Do patient‐reported measures of symptoms and health status predict mortality in hemodialysis? An assessment of POS‐S Renal and EQ‐5D
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Donal J. Sexton Conall M. O'Seaghdha Marie Murphy Tony O'Brien Liam F. Casserly Regina McQuillan William D. Plant Joseph A. Eustace Sinead M. Kinsella Peter J. Conlon 《Hemodialysis international. International Symposium on Home Hemodialysis》2016,20(4):618-630
Introduction Experience with the use of patient‐reported outcome measures such as EQ‐5D and the symptom module of the Palliative care Outcome Scale—Renal Version (POS‐S Renal) as mortality prediction tools in hemodialysis is limited. Methods A prospective survival study of people receiving hemodialysis (N = 362). The EQ‐5D and the POS‐S Renal were used to assess symptom burden and self‐rated health (with a self‐rated component). Participants were followed from instrument completion to death or study end. Competing risks survival analysis was used to evaluate associations with time to death, with renal transplant as a competing risk. Findings 32% (N = 116) of participants died over a median (25th–75th centile) of 2.6 (1.41–3.38) years. Factors most notably associated with mortality adjusted hazard ratio (95%CI) included: lower EQ VAS score 2.7 (1.4, 5.2) P = 0.004 (lowest tertile), higher POS‐S Renal score 2.4 (1.3, 4.3) P = 0.004 (highest tertile), and lower EQ‐5D score 2.6 (1.3, 5.3) P = 0.01 (lowest tertile) as well as the presence of: “problems with mobility?” 2 (1.1, 3.3) P = 0.01, or “problems with usual activities?” 2.1 (1.4, 3.3), P < 0.001. After age adjustment area under the receiver operating curves (AUC) (95%CI) for mortality were: 0.71 (0.62, 0.79) for EQ VAS score, 0.71 (0.63, 0.80) for POS‐S Renal‐S Renal score, and 0.76 (0.68, 0.84) for EQ‐5D score. AUC 95%CI was highest for our fourth model at 0.79 (0.72, 0.86) comprised of individual elements from both instruments and established risk factors. Discussion EQ VAS scores and predictive models based on combinations of elements from the POS‐S Renal and EQ‐5D instruments may aid in mortality discrimination and possibly in the delivery of supportive care services. 相似文献
105.
RNA molecules are crucial in different levels of cellular function, ranging from translation and regulating genes to coding for proteins. Additionally, nucleic acids (RNA and DNA molecules) are designed for novel applications in biotechnology. Understanding the structure of a molecule is important in inferring its function, and computational methods for structure prediction have captured the interest of many researchers.Some functions of RNA molecules in cells, such as gene regulation, result from the binding of one RNA molecule to another, so-called target RNA molecule. This has led to recent interest in prediction of the secondary structure formed from interacting molecules. In this paper, we provide a brief overview of methods, applications, and challenges in computational prediction of nucleic acid secondary structure, both for single strands and for interacting strands. 相似文献
106.
Gabriela Avram Liam Bannon John Bowers Anne Sheehan Daniel K. Sullivan 《Computer Supported Cooperative Work (CSCW)》2009,18(5-6):477-507
This paper reports on results from a long-term field study of globally distributed software development projects within a multinational organization. The research explores the issues involved in performing global software development, utilizing a perspective informed by CSCW research concerning the local organization of work practices and the key role of workers in being able to intervene in the ‘flow of work’ where necessary. The paper also raises some more general questions concerning the field of Global Software Development (GSD), in terms of the concepts and methods being used in the area. Our contribution is in the form of a CSCW-informed empirical study of the use of defect (or ‘bug’) tracking systems—systems which support the identification, classification and resolution of defects in the emerging software. In one case, the team persisted with a defect tracking system that they had used for years and maintained it in parallel with a system used by co-workers in other countries—all the while attempting to implement a bridge between the two. In the other, we report on how local software patches were created to allow for local work to proceed while not interfering with the existing coordination mechanisms between the local site and remote co-workers who were responsible for creating daily builds according to the overall project plan. In both cases, local practices were shaped by the necessity to keep work flowing across the whole project, even if this involved what might, at first sight, seem to go against project-wide practice. We discuss implications of these findings in terms of a key distinction between externally-prescribed ‘workflow’ and internally-managed ‘flow of work’ activities. We also explore how a heterogeneous ‘assembly’ of variably coupled systems may be the most appropriate image for technological support of distributed teams as they keep the work flowing in an orderly fashion. Overall, our work suggests that studies of global software development can profit from the CSCW tradition of workplace studies both conceptually and methodologically. 相似文献
107.
To perform automatic, unconscious inference, the human brain must solve the binding problem by correctly grouping properties with objects. Temporal binding models like SHRUTI already suggest much of how this might be done in a connectionist and localist way by using temporal synchrony. We propose a set of alternatives to temporal synchrony mechanisms that instead use short signatures. This serves two functions: it allows us to explore an additional biologically plausible alternative, and it allows us to extend and improve the capabilities of these models. These extensions model the human ability to both perform unification and handle multiple instantiations of logical terms. To verify our model's feasibility, we simulate it with a computer system modeling simple, neuron-like computations. 相似文献
108.
Sherri Condon Mark Arehart Dan Parvaz Gregory Sanders Christy Doran John Aberdeen 《Machine Translation》2012,26(1-2):159-176
The Defense Advanced Research Projects Agency (DARPA) Spoken Language Communication and Translation System for Tactical Use (TRANSTAC) program (http://1.usa.gov/transtac) faced many challenges in applying automated measures of translation quality to Iraqi Arabic–English speech translation dialogues. Features of speech data in general and of Iraqi Arabic data in particular undermine basic assumptions of automated measures that depend on matching system outputs to reference translations. These features are described along with the challenges they present for evaluating machine translation quality using automated metrics. We show that scores for translation into Iraqi Arabic exhibit higher correlations with human judgments when they are computed from normalized system outputs and reference translations. Orthographic normalization, lexical normalization, and operations involving light stemming resulted in higher correlations with human judgments. 相似文献
109.
Evaluations of the (infrared)-brazed Ti-6Al-4V and niobium joints using three silver-base braze alloys have been extensively
studied. According to the dynamic wetting angle measurement results, the niobium substrate cannot be effectively wetted by
all three braze alloys. Because the dissolution of Ti-6Al-4V substrate causes transport of Ti into the molten braze, the molten
braze dissolved with Ti can effectively wet the niobium substrate during brazing. For infrared-brazed Ti-6Al-4V/Ag/Nb joint,
it is mainly comprised of the Ag-rich matrix. The TiAg reaction layer is observed at the interface between the braze and Ti-6Al-4V
substrate. In contrast, Ti-rich, Ag-rich, and interfacial TiAg phases are found in the furnace-brazed specimen. The dominated
Ti-rich phase in the joint is caused by enhanced dissolution between the molten braze and Ti-6Al-4V substrate. The infrared-brazed
Ti-6Al-4V/72Ag-28Cu/Nb joint is mainly comprised of the Ag-rich matrix and Ag-Cu eutectic. With increasing the brazing temperature
or time, the amount of Ag-Cu eutectic is decreased, and the interfacial Cu-Ti reaction layer(s) is increased. The infrared
brazed joint has the highest average shear strength of 224.1 MPa. The averaged shear strength of the brazed joint is decreased
with increasing brazing temperature or time, and its fracture location changes from the braze alloy into the interfacial reaction
layer(s) due to excessive growth of the Cu-Ti intermetallics. The infrared-brazed Ti-6Al-4V/95Ag-5Al/Nb joint is composed
of Ag-rich matrix and TiAl interfacial reaction layer. With increasing the brazing time, the amount of Ag-rich phase is greatly
decreased, and the interfacial reaction layer becomes Ti3Al due to enhanced dissolution of Ti-6Al-4V substrate into the molten braze. The average shear strength of the infrared-brazed
joint is 172.8 MPa. Additionally, the existence of an interfacial Ti3Al reaction layer significantly deteriorates the shear strength of the furnace-brazed specimen. 相似文献
110.
Optimum adaptation trajectories for streamed multimedia 总被引:1,自引:0,他引:1
Most adaptive delivery mechanisms for streaming multimedia content do not explicitly consider user-perceived quality when
making adaptations. We propose that an optimal adaptation trajectory through the set of possible encodings exists and that
it indicates how to adapt encoding quality in response to changes in network conditions to maximize user-perceived quality.
Such an optimum adaptation trajectory can be used with any transmission adaptation policy. We describe the subjective tests
we carried out to find such trajectories for a number of different MPEG-4 video clips and indicate how this knowledge could
be used in the operation of a practical system. 相似文献