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排序方式: 共有342条查询结果,搜索用时 15 毫秒
61.
Development of drug-delivery systems that selectively target neoplastic cells has been a major goal of nanomedicine. One major strategy for achieving this milestone is to install ligands on the surface of nanocarriers to enhance delivery to target tissues, as well as to enhance internalization of nanocarriers by target cells, which improves accuracy, efficacy, and ultimately enhances patient outcomes. Herein, recent advances regarding the development of ligand-installed nanocarriers are introduced and the effect of their design on biological performance is discussed. Besides academic achievements, progress on ligand-installed nanocarriers in clinical trials is presented, along with the challenges faced by these formulations. Lastly, the future perspectives of ligand-installed nanocarriers are discussed, with particular emphasis on their potential for emerging precision therapies.  相似文献   
62.
The Journal of Supercomputing - Molecular docking techniques are widely used in computational drug discovery. Most of these techniques simulate the way that a ligand interacts with a protein target...  相似文献   
63.
The standard way of evaluating the separation factor for the isotopic separation of U235/238 in the conventional uranium enrichment process by gaseous diffusion through membranes, considers only an average value for the pore radius. This is equivalent to assuming a membrane with all pores of the same size. In this work we discuss the influence of a realistic pore size distribution on the indicated factor and the physical interpretation of these results.  相似文献   
64.
The accuracy of self-report of breast implants was analyzed using a random sample of 130 of 850 available records from a retrospective cohort study of women who underwent cosmetic surgical procedures from 1963 to 1985. Women with breast implants correctly reported having the surgery 89.3 percent of the time, whereas women having other cosmetic surgical procedures correctly reported having the index surgery 92.7 percent of the time. Younger age at surgery, younger age at survey response, and higher level of education were significantly associated with higher sensitivity of self-report. Despite high validity of reporting of surgery, accuracy of self-report of time of surgery was low, with only 9 percent of women who reported their breast implant surgery providing the correct month and year of surgery. These results are in contrast with a previous validity study.  相似文献   
65.
The blood flow rates of 14 tissues in the body were determined by microsphere method using normal and tumor-bearing rats kept conscious or under urethane anesthesia. The effects on the blood flow rate in the tissues were assessed for multimodal therapy, systemic hypothermia for ischemic brain injury, and local hyperthermia and angiotensin II-induced hypertensive chemotherapy for cancer. Urethane anesthesia showed no effect on cardiac output, while there was a tendency of decrease of blood flow rate and % of cardiac output in each tissue other than muscle tissue, in which they increased as a counterbalance, in normal and tumor-bearing rats. Systemic hypothermia gave results similar to those of urethane anesthesia in normal rats, but for tumor-bearing rats, it decreased cardiac output, and consequently the blood flow rate in most tissues. Brain blood flow rate was about half of that in the conscious rats. Local hyperthermia also decreased the cardiac output and blood flow rate in each tissue, including the tumor tissue. Angiotensin II-induced hypertension showed no effect on cardiac output, had various effects on blood flow rate in each tissue, and led to no increase in the tumor blood flow rate. Simulations based on the physiological pharmacokinetic modeling suggested that intramuscular injection of a lung-specific derivative of ceftazidime would provide the ideal biodistribution to ensure its optimal therapeutic efficacy during systemic hypothermia. This methodology, namely the pharmacokinetic simulation based on the physiological values of the body, will provide a useful piece of information on drug delivery systems under various conditions.  相似文献   
66.
CO hydrogenation over Mn-promoted Rh/NaY catalysts was studied at 1 MPa and 250°C. Significant selectivity to ethanol and ethyl acetate was obtained only after neutralising the protons formed on reduction of Rh ions. Layered bed experiments show that protons act as Brønsted acid sites catalysing secondary reactions that convert the oxygenates to hydrocarbons and coke.  相似文献   
67.
Software and Systems Modeling - The Discrete Event System Specification (DEVS) is a modular and hierarchical Modeling and Simulation (M&S) formalism based on systems theory that provides a...  相似文献   
68.
In this paper, we consider the filtering problem for Lipschitz systems in a networked environment. We assume that the measurements transmitted over the network are subject to quantization, uncertain delays and communication constraints. We first analytically demonstrate how each of the these issues affect the filtering problem. Second, we tackle the filter design as an optimization problem with LMI constraints. The optimization maximizes the Lipschitz constant and thus the region of attraction for which the filter is stable and an bound is satisfied by the error system. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
69.
This article presents the Spanish Iarg-AnCora corpus (400 k-words, 13,883 sentences) annotated with the implicit arguments of deverbal nominalizations (18,397 occurrences). We describe the methodology used to create it, focusing on the annotation scheme and criteria adopted. The corpus was manually annotated and an interannotator agreement test was conducted (81 % observed agreement) in order to ensure the reliability of the final resource. The annotation of implicit arguments results in an important gain in argument and thematic role coverage (128 % on average). It is the first corpus annotated with implicit arguments for the Spanish language with a wide coverage that is freely available. This corpus can subsequently be used by machine learning-based semantic role labeling systems, and for the linguistic analysis of implicit arguments grounded on real data. Semantic analyzers are essential components of current language technology applications, which need to obtain a deeper understanding of the text in order to make inferences at the highest level to obtain qualitative improvements in the results.  相似文献   
70.
The characterization and improvement of a rectangular channel electrolyte flow compartment used in an iron‐air flow battery was carried out by using an arrangement of copper electrodes to measure the current density distribution employing the limiting current technique. The present work addresses the hydrodynamics and mass transport distribution in the compartment and their improvement by an improved electrolyte compartment that results in a more uniform current distribution. The current distribution was evaluated as the ratio between the local and the averaged limiting current densities during the reduction of copper ions over a range of mean linear flow velocity across the electrode surface (2–30 cm s?1). The initial compartment, showed larger differences between the minimum and maximum currents than the electrolyte compartment that resulted as part of the design process and showed a higher pressure drop at a given mean linear flow velocity. © 2016 American Institute of Chemical Engineers AIChE J, 63: 1144–1151, 2017  相似文献   
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