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排序方式: 共有600条查询结果,搜索用时 15 毫秒
1.
Anja Schrder Joris Sprakel Karin Schroën Claire C. Berton‐Carabin 《European Journal of Lipid Science and Technology》2020,122(6)
Colloidal lipid particles (CLPs) are promising encapsulation systems for lipophilic bioactives, such as oil‐soluble antioxidants that are applied in food and pharmaceutical formulations. Currently, there is no clear consensus regarding the relation between particle structure and the chemical stability of such bioactives. Using α‐tocopherol as a model antioxidant, it is shown that emulsifier type (Tween 20 or 40, or sodium caseinate) and lipid composition (tripalmitin, tricaprylin, or combinations thereof) modulated particle morphology and antioxidant stability. The emulsifier affects particle shape, with the polysorbates facilitating tripalmitin crystallization into highly ordered lath‐like particles, and sodium caseinate resulting in less ordered spherical particles. The fastest degradation of α‐tocopherol is observed in tripalmitin‐based CLPs, which may be attributed to its expulsion to the particle surface induced by lipid crystallization. This effect is stronger in CLPs stabilized by Tween 40, which may act as a template for crystallization. This work not only shows how the architecture of CLPs can be controlled through the type of lipid and emulsifier used, but also gives evidence that lipid crystallization does not necessarily protect entrapped lipophilic bioactives, which is an important clue for encapsulation system design. Practical Applications: Interest in enriching food and pharmaceutical products with lipophilic bioactives such as antioxidants through encapsulation in lipid particles is growing rapidly. This research suggests that for efficient encapsulation, the particle architecture plays an important role; to tailor this, the contribution of both the lipid carrier and the emulsifier needs to be considered. 相似文献
2.
This paper presents a detailed analysis of the rotor–tower interaction and the effects of the rotor's tilt angle and yaw misalignment on a large horizontal axis wind turbine. A high‐fidelity aeroelastic model is employed, coupling computational fluid dynamics (CFD) and structural mechanics (CSM). The wind velocity stratification induced by the atmospheric boundary layer (ABL) is modeled. On the CSM side, the complex composite structure of each blade is accurately modeled using shell elements. The rotor–tower interaction is analyzed by comparing results of a rotor‐only simulation and a full‐machine simulation, observing a sudden drop in loads, deformations, and power production of each blade, when passing in front of the tower. Subsequently, a tilt angle is introduced on the rotor, and its effect on blade displacements, loads, and performance is studied, representing a novelty with respect to the available literature. The tilt angle leads to a different contribution of gravity to the blade deformations, sensibly affecting the stresses in the composite material. Lastly, a yaw misalignment is introduced with respect to the incoming wind, and the resulting changes in the blade solicitations are analyzed. In particular, a reduction of the blade axial displacement amplitude during each revolution is observed. 相似文献
3.
Microbially mediated phosphine emission 总被引:1,自引:0,他引:1
There is still a lot of controversy in literature concerning the question whether a biochemical system exists enabling micro-organisms to reduce phosphate to phosphine gas. The search for so-called 'de novo synthesised' phosphine is complicated by the fact that soils, slurries, sludges, etc., which are often used as inocula, usually contain matrix bound phosphine (MBP). Matrix bound phosphine is a general term used to indicate non-gaseous reduced phosphorus compounds that are transformed into phosphine gas upon reaction with bases or acids. A study was carried out to compare the different digestion methods, used to transform matrix bound phosphine into phosphine gas. It was demonstrated that caustic and acidic digestion methods should be used to measure the matrix bound phosphine of the inoculum prior to inoculation to avoid false positive results concerning de novo synthesis. This is especially true if anthropogenically influenced inocula possibly containing minute steel or aluminium particles are used. The comparative study on different digestion methods also revealed that the fraction of phosphorus in mild steel, converted to phosphine during acid corrosion depended on the temperature. Following these preliminary studies, anaerobic growth experiments were set up using different inocula and media to study the emission of phosphine gas. Phosphine was detected in the headspace gases and its quantity and timeframe of emission depended on the medium composition, suggesting microbially mediated formation of the gas. The amount of phosphine emitted during the growth experiments never exceeded the bound phosphine present in inocula, prior to inoculation. Hence, de novo synthesis of phosphine from phosphate could not be demonstrated. Yet, microbially mediated conversion to phosphine of hitherto unknown reduced phosphorus compounds in the inoculum was evidenced. 相似文献
4.
A Novel Technology for Natural Gas Conversion by Means of Integrated Oxidative Coupling and Dry Reforming of Methane 下载免费PDF全文
Dr. Joris W. Thybaut Prof. Guy B. Marin Dr. Claude Mirodatos Dr. Yves Schuurman Dr. Andre C. van Veen Prof. Vladislav A. Sadykov Dr. Helmut Pennemann Dr. Rainer Bellinghausen Prof. Leslaw Mleczko 《化学,工程师,技术》2014,86(11):1855-1870
A novel process concept for the oxidative coupling of methane followed by the oligomerization to liquids has been developed within the frame of the EU integrated project OCMOL. This technology is based on process intensification principles via cutting‐edge structured microreactor technology. It is also a fully integrated industrial process through the re‐use and the recycling of by‐products, in particular CO2, at every process stage. The focus of this contribution is on the reaction engineering aspects of the core steps, i.e., catalysts, kinetics and reactor design for the methane coupling and reforming. 相似文献
5.
6.
Sticker complexes are a formal graph-based data model for a restricted class of DNA complexes, motivated by potential applications to databases. This data model allows for a purely declarative definition of hybridization. We introduce the notion of terminating hybridization, which intuitively means that only a finite number of different products can be generated. We characterize this notion in purely graph-theoretic terms. Under a finite alphabet, each product is shown to be of polynomial size. Yet, terminating hybridization can still produce results of exponential size, in that there may be exponentially many different (nonisomorphic) finished products. We indicate a class of complexes where hybridization is guaranteed to be polynomially bounded. 相似文献
7.
Peter Dedecker Jeroen Hoebeke Ingrid Moerman Joris Moreau Piet Demeester 《Telecommunication Systems》2013,52(4):1859-1876
In this paper the Virtual Private Ad Hoc Networking (VPAN) platform is introduced as an integrated networking solution for many applications that require secure transparent continuous connectivity using heterogeneous devices and network technologies. This is done by creating a virtual logical self-organizing network on top of existing network technologies reducing complexity and maintaining session continuity right from the start. One of the most interesting applications relies in the field of emergency communication with its specific needs which will be discussed in this paper and matched in detail against the architecture and features of the VPAN platform. The concept and dynamics are demonstrated and evaluated with measurements done on real hardware. 相似文献
8.
Joris C. Verster Juergen Koenig 《Critical reviews in food science and nutrition》2018,58(8):1250-1259
Aim of this review is to summarize current daily caffeine intake of children, adolescents, and adults, and trends in caffeine intake over the past decade. A literature search was conducted (1997–2015) which yielded 18 reports on nationally representative studies, describing caffeine consumption of over 275,000 children, adolescents and adults. The data revealed that mean total daily caffeine intake in children, adolescents, and adults is below caffeine intake recommendations such as those stated by Health Canada (2.5 mg/kg bw/day for children and adolescents, and 400 mg/day for adults) and the European Food Safety Authority, EFSA (3 mg/kg bw/day for children and adolescents, and 400 mg/day for adults). Total daily caffeine intake has remained stable in the last 10–15 years, and coffee, tea and soft drinks are the most important caffeine sources. Across all age groups, energy drinks contribute little to total caffeine intake. The highest potential for reducing daily caffeine intake is by limiting coffee consumption, and in some countries and age groups, by reducing tea and soft drink consumption. 相似文献
9.
Tony Wauters Joris Kinable Pieter Smet Wim Vancroonenburg Greet Vanden Berghe Jannes Verstichel 《Journal of Scheduling》2016,19(3):271-283
Scheduling projects is a difficult and time consuming process, and has far-reaching implications for any organization’s operations. By generalizing various aspects of project scheduling, decision makers are enabled to capture reality and act accordingly. In the context of the MISTA 2013 conference, the first MISTA challenge, organized by the authors, introduced such a general problem model: the Multi-Mode Resource-Constrained Multi-Project Scheduling Problem (MRCMPSP). The present paper reports on the competition and provides a discussion on its results. Furthermore, it provides an analysis of the submitted algorithms, and a study of their common elements. By making all benchmark datasets and results publicly available, further research on the MRCMPSP is stimulated. 相似文献
10.
Johannes Jacobi Renke Maas Michaela Arend Nada Cordasic Karl F. Hilgers 《International journal of molecular sciences》2014,15(4):5522-5535
The purpose of the work was to study the impact of the endogenous nitric oxide synthase (NOS) inhibitor asymmetric dimethylarginine (ADMA) and its degrading enzyme, dimethylarginine dimethylaminohydrolase (DDAH1), on atherosclerosis in subtotally nephrectomized (SNX) ApoE-deficient mice. Male DDAH1 transgenic mice (TG, n = 39) and C57Bl/6J wild-type littermates (WT, n = 27) with or without the deletion of the ApoE gene underwent SNX at the age of eight weeks. Animals were sacrificed at 12 months of age, and blood chemistry, as well as the extent of atherosclerosis within the entire aorta were analyzed. Sham treated (no renal mass reduction) ApoE-competent DDAH1 transgenic and wild-type littermates (n = 11) served as a control group. Overexpression of DDAH1 was associated with significantly lower ADMA levels in all treatment groups. Surprisingly, SNX mice did not exhibit higher ADMA levels compared to sham treated control mice. Furthermore, the degree of atherosclerosis in ApoE-deficient mice with SNX was similar in mice with or without overexpression of DDAH1. Overexpression of the ADMA degrading enzyme, DDAH1, did not ameliorate atherosclerosis in ApoE-deficient SNX mice. Furthermore, SNX in mice had no impact on ADMA levels, suggesting a minor role of this molecule in chronic kidney disease (CKD) in this mouse model. 相似文献