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331.
Elke Steeg und Alfred Montag 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1988,187(2):115-120
Zusammenfassung Honige der Trachten Buchweizen, Löwenzahn, Raps, Heide, Wald und Konifere wurden auf freie und alkalisch hydrolysierbare gebundene aromatische Carbonsäuren, die im Phenylpropan-Metabolismus von höheren Pflanzen gebildet werden, untersucht. Letztere können weder über ihre qualitative noch über ihre quantitative Verteilung zu einer Trachtunterscheidung beitragen. Die freien Säuren lassen jedoch ein pflanzenabhängiges Verteilungsmuster in den Honigen erkennen. Rapshonige sind durch das Vorkommen von Phenylpropionsäure charakterisiert, Buchweizenhonige durch das Fehlen von Phenylessigsäure und die erhöhten Gehalte an 4-Hydroxybenzoesäure. Identitätsmerkmale für Heidehonige sind die hohen Gehalte an Benzoesäure, Phenylessigsäure, Mandelsäure und vor allem-Phenylmilchsäure Zwischen Wald- und Koniferenhonigen bestehen keine signifikanten Unterschiede, eine Abgrenzung der Honigtauhonige gegen die Blütenhonige 1äßt sich über die erhöhten Gehalte an Protocatechusäure treffen.
Quantitative determination of aromatic carbonic acids in honey
Summary Floral sources of honeys, namely buck-wheat, dandelion, rape, heather, forest and conifer, were analysed for free and alkali hydroxylable bound aromatic carbonic acids, which arise from phenylpropanoid metabolism. Specific in a plant distribution is only recognizable with the free acids. Rape honeys are characterized by the occurrence of phenylpropanoic acid and buckwheat honeys have a higher content of 4-hydroxybenzoic acid and no phenylacetic acid. Heather honeys can be identified by the presence of a high concentration of benzoic acid, phenylacetic acid, mandelic acid and-phenylactic acid. Differentiation of honeydew honeys and flower honeys is possible because of the difference in the concentration of protocatechuic acid.相似文献
332.
333.
Buzolin Ricardo Henrique Weiß Desirée Krumphals Alfred Lasnik Michael Poletti Maria Cecilia 《Metallurgical and Materials Transactions A》2020,51(8):3967-3980
Metallurgical and Materials Transactions A - The competitive formation of allotriomorphic α along the prior β grain boundaries, secondary α-phase and the growth of globular primary... 相似文献
334.
A Subdivision Scheme for Continuous-Scale B-Splines and Affine-Invariant Progressive Smoothing 总被引:1,自引:0,他引:1
Guillermo Sapiro Albert Cohen Alfred M. Bruckstein 《Journal of Mathematical Imaging and Vision》1997,7(1):23-40
Multiscale representations and progressive smoothing constitutean important topic in different fields as computer vision, CAGD,and image processing. In this work, a multiscale representationof planar shapes is first described. The approach is based oncomputing classical B-splines of increasing orders, andtherefore is automatically affine invariant. The resultingrepresentation satisfies basic scale-space properties at least ina qualitative form, and is simple to implement.The representation obtained in this way is discrete in scale,since classical B-splines are functions in
, where k isan integer bigger or equal than two. We present a subdivisionscheme for the computation of B-splines of finite support atcontinuous scales. With this scheme, B-splines representationsin
are obtained for any real r in [0, ), andthe multiscale representation is extended to continuous scale.The proposed progressive smoothing receives a discrete set ofpoints as initial shape, while the smoothed curves arerepresented by continuous (analytical) functions, allowing astraightforward computation of geometric characteristics of theshape. 相似文献
335.
Beckh Cornelius Sulzer Philipp Fritzsche Niklas Riek Claudius Leitenstorfer Alfred 《Journal of Infrared, Millimeter and Terahertz Waves》2021,42(6):701-714
Journal of Infrared, Millimeter, and Terahertz Waves - We explore background-free options to detect mid-infrared (MIR) electric transients. The MIR field and a near-infrared probe interact via sum-... 相似文献
336.
Younger black patients have a higher risk of infection mortality that is mostly non‐dialysis related: A national study of cause‐specific mortality among U.S. maintenance dialysis patients
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Alison J. Yu Keith C. Norris Alfred K. Cheung Guofen Yan 《Hemodialysis international. International Symposium on Home Hemodialysis》2017,21(2):232-242
Introduction: While it has been well documented that in the U.S., black and Hispanic dialysis patients have overall lower risks of death than white dialysis patients, little is known whether their lower risks are observed in cause‐specific deaths. Additionally, recent research reported that younger black patients have a higher risk of death, but the source is unclear. Therefore, this study examined cause‐specific deaths among US dialysis patients by race/ethnicity and age. Methods: This national study included 1,255,640 incident dialysis patients between 1995 and 2010 in the United States Renal Data System. Five cause‐specific mortality rates, including cardiovascular (CVD), infection, malignancy, other known causes (miscellaneous), and unknown, were compared across blacks, Hispanics, and whites overall and stratified by age groups. Findings: After multiple adjustments, Hispanic patients had the lowest risk of mortality for every major cause in almost all ages. Compared with whites, blacks had a lower risk of death from CVD, malignancy and miscellaneous causes in most age groups, but not from infection. In fact, blacks had a higher risk of infection death than whites in ages 18–30 years (HR [95% CI] 1.94 [1.69–2.23]; P < 0.001), 31–40 years (HR 1.51 [1.40–1.63]; P < 0.001) and 41–50 years (HR 1.07 [1.02–1.12]; P = 0.009), which were partially attributed to their higher prevalence of AIDS nephropathy. For each race/ethnicity, more than two‐thirds of infection deaths were due to non‐dialysis related infections. Discussion: Hispanics had the lowest risk for each major cause of death. Blacks were less likely to die than whites from most causes, except infection. The previously reported higher overall mortality rate for younger blacks is attributed to their two‐fold higher infection mortality, which is mostly non‐dialysis related, suggesting a new direction to improve their overall health status. Research is greatly needed to determine social and biological factors that account for the survival gap in dialysis among different racial/ethnic groups. 相似文献
337.
Joseph Lik Hang Chau Yen-Yu Hou Alfred I-Tsung Pan Chih-Chao Yang 《Particulate Science and Technology》2017,35(2):209-213
Gas atomized Fe50Cr24Mo21Si2B3 powders were used to form Fe-based alloy coatings by the air plasma spray method. The coatings exhibited high amorphous nature and extremely low porosity of 0.41% in about 200 µm thickness. The Fe-based coating exhibits an average hardness about 1255 Hv. The Fe-based coatings could be potentially applied as functional surface protective coatings. 相似文献
338.
Mehdi Rezaeianzadeh Alfred Stein Jonathan Peter Cox 《Water Resources Management》2016,30(7):2245-2259
Water resources management is a complex task. It requires accurate prediction of inflow to reservoirs for the optimal management of surface resources, especially in arid and semi-arid regions. It is in particular complicated by droughts. Markov chain models have provided valuable information on drought or moisture conditions. A complementary method, however, is required that can both evaluate the accuracy of the Markov chain models for predicted drought conditions, and forecast the values for ensuing months. To that end, this study draws on Artificial Neural Networks (ANNs) as a data-driven model. The employed ANNs were trained and tested by means of a statistically-based input selection procedure to accurately predict reservoir inflow and consequently drought conditions. Thirty three years’ data of inflow volume on a monthly time resolution were selected to enable calculation of the standardized streamflow index (SSI) for the Markov chain model. Availability of hydro-climatic data from the Doroodzan reservoir in the Fars province, Iran, allowed us to develop a reservoir specific ANN model. Results demonstrated that both models accurately predicted drought conditions, by employing a randomization procedure that facilitated the selection of the required data for the ANN to forecast reservoir inflow close to the observed values over a validation period. The results confirmed that combining the two models improved short-term prediction reliability. This was in contrast to single model applications that resulted into substantial uncertainty. This research emphasized the importance of the correct selection of data or data mining, prior to entering a specific modeling routine. 相似文献
339.
Definition of the problem
The term Advance Care Planning describes a concept of comprehensive planning for future health care situations that, amongst others, aims at supporting people to set up advance statements defining goals and desired directions of patient care, using qualified, prospective counseling offers. Another aim is to promote the dissemination and implementation of this concept with the help of structural, mostly regional measures.Arguments
This article discusses Advance Care Planning in psychiatry. It visualizes different forms of psychiatric advance statements and reports legal regulations from the US, Great Britain and Germany. Furthermore, this article provides an overview of international studies on the implementation of Advance Care Planning in psychiatry. These studies impressively illustrate the need of qualified counseling- and supportive offers, as without such offers, advance statements are hardly implemented and noticed in practice.Conclusion
Against this background, the authors recommend the experimental implementation of (regional) Advance Care Planning programs as pilot projects, aiming at ameliorating quality and acceptance of advance statements in psychiatry. These projects should be scientifically accompanied, evaluated and where necessary adjusted.340.
Interfacial film properties of asphaltenes and resins 总被引:1,自引:0,他引:1
Interfacial film properties of asphaltenes and resins have been studied by interfacial shear viscosity measurements. The results show that the structure of the asphaltene film at the interface between oil and water is changed from two-dimensional to three-dimensional network as the concentration of the asphaltene at the interface increased. The film can be divided into three types namely expanded liquid film, condensed liquid film and solid-like three-dimensional network film. Furthermore, the structures of the interfacial films formed by asphaltene molecules and asphaltene particles are different and the strengths of these films are also different. The adsorption and migration processes of asphaltene molecules and migration process of asphaltene particles at the interface are different. 相似文献