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81.
82.
A black hole is a region of space that has so much mass concentrated in it that there is no way training data for a nearby object to escape its gravitational pull. In this paper we are inspired by this phenomenon to create a new form of novelty detector. We consider the of a given class as a black hole. For multi-class data we are dealing with multiple black holes. A test point is pulled by the centroids of different black holes as well as its K nearest neighbours. The gravitational pull is modelled as an iterative process, where the forces acting on a point are constantly changing with time as the test point moves in multi-dimensional space corresponding to these forces. Once the algorithm has converged, a thresholding scheme is applied to determine whether the test point has been pulled within the boundary of the black hole or not. Any points that lie outside all known black holes are deemed to be novel. We compare this novelty detector with other well-known models of novelty detection on a video analysis application and show very promising results. 相似文献
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84.
Malek Alkasrawi Alex S. Rajangam Muhammad Tawalbeh Feras Kafiah Amani Al-Othman Sameer Al-Asheh Qiang Sun 《国际能源研究杂志》2020,44(15):12602-12613
A novel bioprocess design to convert paper mill sludge (PMS) to biofuels is proposed in this work. The design utilizes cellulosic fiber recovered from the PMS via optimized de-ashing (HCl washing) step. This work specifically provided a technical and economic analysis of paper mill sludge conversion into biofuel production using a novel protocol. The protocol is based on scanning electron microscopy (SEM) analysis to assess the quality of the contained cellulose prior to further processing. The results are crucially important to determine the suitability of the PMS feedstock to produce biofuels. SEM analysis was employed as a preliminary screening tool to evaluate sludge digestibility and conversion. The SEM characterization technique established a direct relationship between the fiber morphology, presence of crystals salts and sugar yield after enzymatic hydrolysis. Substantial structural changes were observed before and after de-ashing the sludge samples, leading to a correlation between the surface morphology and the washing step. The results suggested that de-ashing changes the surface morphology and upon analysis, increased the sugar yield up to about 86% as opposed to 2.2% in sludge sample A as an example. The PMS conversion into biofuel was simulated using Aspen PLUS and compared to a similar process using corn stover as feedstock. The simulation results showed it is 20% cheaper to produce bioethanol from PMS compared to corn stover. The simulation revealed less energy demand by around 13 320 MJ/h compared to that when corn stover was used. 相似文献
85.
Among lipid-based nanocarriers, multi-layered cochleates emerge as a novel delivery system because of prevention of oxidation of hydrophobic and hydrophilic drugs, enhancement in permeability, and reduction in dose of drugs. It also improves oral bioavailability and increases the safety of a drug by targeting at a specific site with less side effects. Nanostructured cochleates are used as a carrier for the delivery of water-insoluble or hydrophobic drugs of anticancer, antiviral and anti-inflammatory action. This review article focuses on different methods for preparation of cochleates, mechanism of formation of cochleates, mechanism of action like cochleate undergoes macrophagic endocytosis and release the drug into the systemic circulation by acting on membrane proteins, phospholipids, and receptors. Advanced methods such as calcium-substituted and β-cyclodextrin-based cochleates, novel techniques include microfluidic and modified trapping method. Cochleates showed enhancement in oral bioavailability of amphotericin B, delivery of factor VII, oral mucosal vaccine adjuvant-delivery system, and delivery of volatile oil. In near future, cochleate will be one of the interesting delivery systems to overcome the stability and encapsulation efficiency issues associated with liposomes. The current limiting factors for commercial preparation of cochleates involve high cost of manufacturing, lack of standardization, and specialized equipments. 相似文献
86.
Scientometrics - Journal impact indicators are useful measures to determine the relative importance of journals within a given discipline. By recasting the journal cross-citation matrix as a... 相似文献
87.
Sameer R. Paital Wei He Claus Daniel Narendra B. Dahotre 《JOM Journal of the Minerals, Metals and Materials Society》2010,62(6):76-83
Wetting is an important aspect for implantable biomaterials, as it affects the initial interaction with physiological fluids,
which in turn dictates the protein adsorption, cell attachment, and tissue integration at the interface. In light of this
in the present overview, surface engineering techniques based on laser processing of implantable titanium alloys for improved
wettability and cell compatibility is discussed. Here three different laser processing techniques, laser interference patterning,
continuous wave laser direct melting, and pulsed laser direct melting and the influence of each type of processing on the
micro-texture evolution are studied Finally, the effect of micro-textures on the wettability and thereby its in vitro bioactivity
and in vitro biocompatibility is systematically discussed. 相似文献
88.
Sameer Singh 《Pattern Analysis & Applications》2000,3(1):1-8
Pattern Analysis and Applications - 相似文献
89.
As online social networking has become an immersive and pervasive phenomenon, traditional considerations and expectations of personal privacy have been drastically altered. This paradigmatic change has led to adolescents possibly making themselves vulnerable to embarrassment, censure, damage to one’s name or reputation, or even victimization by others because of unwise postings or revelations online. The current study sought to determine the extent to which adolescent information disclosure on MySpace.com has changed between 2006 and 2009. We found significant changes in the nature of personal content made publicly available across the two time points and a trend in which teens are being increasingly more selective and discrete when it comes to what they share and with whom they share it. 相似文献
90.
Free-standing films of multi-walled carbon nanotubes (MWCNTs), also known as buckypapers, have been fabricated by a two-step process using electrophoretic deposition (EPD). Films of the multi-walled carbon nanotubes were cast onto stainless steel electrodes from aqueous suspensions by EPD. Using a facile mechanical cleavage technique, the films were liberated from their underlying electrodes to yield the buckypapers. We investigated the films’ thickness, morphology, and surface topology using, respectively, profilometry, scanning electron microscopy, and atomic force microscopy. Mechanical characterization of the buckypapers revealed the average tensile strength and Young’s modulus to be 14.5 MPa and 3.3 GPa, respectively. This fabrication approach provides a cost effective, rapid, and reproducible method to make films of MWCNTs with a range of thicknesses and macroscopic lateral dimensions. 相似文献