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41.
High triacylglycerol (TAG) levels may predict vascular risk. The effect of a statin-induced reduction in TAG levels, irrespective of HDL-C increase, on clinical outcome has not yet been addressed by an endpoint study in patients with coronary heart disease (CHD). The GREACE study compared usual with structured care aimed at achieving LDL-C = 100 mg/dL (2.6 mmol/L) by dose titration with atorvastatin. All patients had CHD and were followed for 3 years. This post hoc analysis of GREACE examines the effect of statins on TAG levels and their relation with cardiovascular disease (CVD) events in all patients and in the subgroup of patients with metabolic syndrome (MetS). Baseline TAG levels >150 mg/dL (1.7 mmol/L) were predictive of subsequent CVD events [cardiac mortality, non-fatal myocardial infarction (MI), unstable angina (UA), revascularisation, congestive heart failure (CHF), and stroke] only in statin untreated patients. Stepwise regression analysis showed that with every 20% statin-related TAG reduction there was a decrease in CVD risk by 12% (HR 0.88, 95% CI 0.75–0.95, P = 0.007) in the structured care group vs. the usual care group, by 8% (HR 0.92, 95% CI 0.81–0.97, P = 0.02) in all statin treated patients vs. the untreated ones and by 15% (HR 0.85, 95% CI 0.65–0.94, P = 0.005) in those with MetS treated with a statin vs. those untreated. Using the same analysis but only taking into consideration vascular events (cardiac mortality, non-fatal MI, UA, revascularisation, and stroke) there was a 18% (HR = 0.82, 95% CI 0.57–0.96, P = 0.03) decrease in risk in the MetS (+) patients treated with a statin vs. those not on a statin, and a decrease in risk by 16% (HR = 0.84, 95% CI 0.53–1.07, P = 0.08), when only hard vascular endpoints (cardiac mortality, non-fatal MI, and stroke) were considered. TAG levels are predictive of subsequent CVD events in statin untreated CHD patients. Statin (mainly atorvastatin)-induced decrease in TAG levels was related to a significant reduction in subsequent CVD events. This benefit was more pronounced in CHD MetS (+) patients.  相似文献   
42.
This work was dedicated to reporting the full chemical and physical characterisation of Crambe abyssinica Hochst. seed oil. The oil from the seeds was extracted using n-hexane. The seeds contain about 30?% oil. Density, refractive index, colour, smoke point, viscosity, acidity, saponification value, iodine value, fatty acid methyl esters, the relative position of fatty acids in C1 and C3 carbon glycerol, sterols, tocopherols, peroxide value, $ \mathop E\nolimits_{{1{\text{cm}}}}^{1\,\% } $ at 232?nm, and the susceptibility to oxidation measured by the Rancimat method were determined. The oil was found to contain high levels of unsaturated fatty acids, especially C22:1 (63.77?%). The dominant saturated acid was C22:0 (2.14?%). The oil was also found to contain high levels of β-sitosterol (51.93?%), campestanol (21.98?%), and brassicasterol (12.35?%). α-, γ-, and δ-Tocopherols were detected up to levels of 7.67, 125.04, and 3.99?mg/kg, respectively. The induction period (at 110?°C and 20?l/h) of the oil was 8.83?h. The relative position of fatty acids in C1 and C3 position was as follows: linoleic 0.45?%, oleic 8.84?%, and erucic 90.72?%. The thermal profile of the oil presented a single peak at ?20.94?°C.  相似文献   
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A novel process flowsheet is presented that co-produces hydrogen and formic acid from natural gas, without emitting any carbon dioxide. The principal technologies employed in the process network include combustion, steam methane reforming (SMR), pressure swing adsorption, and formic acid production from CO2 and H2. Thermodynamic analysis provides operating limits for the proposed process, and the use of reaction clusters leads to the synthesis of a feasible process flowsheet. Heat and power integration studies show this flowsheet to be energetically self-sufficient through the use of heat engine and heat pump subnetworks. Operating cost/revenue studies, using current market prices for natural gas, hydrogen and formic acid, identify the proposed design’s operating revenue to cost ratio to be 9.29.  相似文献   
45.
Stoichoimetric graphene fluoride monolayers are obtained in a single step by the liquid-phase exfoliation of graphite fluoride with sulfolane. Comparative quantum-mechanical calculations reveal that graphene fluoride is the most thermodynamically stable of five studied hypothetical graphene derivatives; graphane, graphene fluoride, bromide, chloride, and iodide. The graphene fluoride is transformed into graphene via graphene iodide, a spontaneously decomposing intermediate. The calculated bandgaps of graphene halides vary from zero for graphene bromide to 3.1 eV for graphene fluoride. It is possible to design the electronic properties of such two-dimensional crystals.  相似文献   
46.
In this work, we present a methodology for the global optimization of reactive distillation (RD) networks, through the Infinite DimEnsionAl State-space (IDEAS) approach. Within the IDEAS framework, network synthesis is formulated as an infinite dimensional linear optimization problem. The IDEAS conceptual framework is realized through solution of a series of finite dimensional linear programs whose optimum values converge to the infinite program’s infimum. The proposed optimal design methodology is demonstrated on a case study involving reactive distillation-based synthesis of methyl tert-butyl ether (MTBE) from isobutene and methanol.  相似文献   
47.
Many structured overlay networks rely on a ring invariant as a core network connectivity element. The responsibility ranges of the participating peers and navigability principles (greedy routing) heavily depend on the ring structure. For correctness guarantees, each node needs to eagerly maintain its immediate neighboring links - the ring invariant. However, the ring maintenance is an expensive task and it may not even be possible to maintain the ring invariant continuously under high churn, particularly as the network size grows. Furthermore, routing anomalies in the network, peers behind firewalls and Network Address Translators (NATs) create non-transitivity effects, which inevitably lead to the violation of the ring invariant. We argue that reliance on the ring structure is a serious impediment for real life deployment and scalability of structured overlays. In this paper we propose an overlay called Fuzzynet, which does not rely on the ring invariant, yet has all the functionalities of structured overlays. Fuzzynet takes the idea of lazy overlay maintenance further by dropping any explicit connectivity and data maintenance requirement, relying merely on the actions performed when new Fuzzynet peers join the network. We show that with sufficient amount of neighbors (O(log N), comparable to traditional structured over-lays), even under high churn, data can be retrieved in Fuzzynet w.h.p. We validate our novel design principles by simulations as well as PlanetLab experiments and compare them with ring based overlays.  相似文献   
48.
How to adapt applications for the Cloud environment   总被引:1,自引:1,他引:0  
The migration of existing applications to the Cloud requires adapting them to a new computing paradigm. Existing works have focused on migrating the whole application stack by means of virtualization and deployment on the Cloud, delegating the required adaptation effort to the level of resource management. With the proliferation of Cloud services allowing for more flexibility and better control over the application migration, the migration of individual application layers, or even individual architectural components to the Cloud, becomes possible. Towards this goal, in this work we focus on the challenges and solutions for each layer when migrating different parts of the application to the Cloud. We categorize different migration types and identify the potential impact and adaptation needs for each of these types on the application layers based on an exhaustive survey of the State of the Art. We also investigate various cross-cutting concerns that need to be considered for the migration of the application, and position them with respect to the identified migration types. Finally, we present some of the open research issues in the field and position our future work targeting these research questions.  相似文献   
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50.
Ultrasonic monitoring of bone fracture healing   总被引:1,自引:0,他引:1  
Quantitative ultrasound has attracted significant interest in the evaluation of bone fracture healing. Animal and clinical studies have demonstrated that the propagation velocity across fractured bones can be used as an indicator of healing. Researchers have recently employed computational methods for modeling wave propagation in bones, aiming to gain insight into the underlying mechanisms of wave propagation and to further enhance the monitoring capabilities of ultrasound. In this paper, we review the relevant literature and present the current status of knowledge.  相似文献   
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