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81.
Pattern Analysis and Applications - One-class classifier (OCC) is involved for solving different kinds of problems due to its ability to represent a class distribution regardless the remaining...  相似文献   
82.
This study aimed to compare the protective effect of two geographically distinct propolis against the formation of advanced glycation end products (AGEs). The polyphenol content of propolis extracts (EEPs) was analysed using HPLC-DAD-MS profiling and evaluated for their protective effects against pentosidine-like AGEs. Dicarbonyl trapping capacities of major EEP compounds were determined using a methylglyoxal scavenging in vitro assay. Both propolis samples were characterised with high levels of pinobanksin derivatives exhibiting strong anti-AGE properties. EEPs reduced AGE formation more effectively than well-known natural AGE inhibitors such as quercetin or chlorogenic acid. Individual evaluations of the five major compounds in EEPs showed that flavonoids strongly inhibit the formation of AGEs by trapping dicarbonyl intermediates, whereas compounds such as caffeic acid derivatives only act as antioxidant agents. Propolis is thus a promising candidate for the prevention and control of AGE-related chronic diseases.  相似文献   
83.
Volume dielectric barrier discharge (VDBD) is considered to be the most effective method for ozone generation. This paper reports a comparison between a simple ‘classic’ VDBD cylindrical ozone generator and a ‘metallic-mesh-filled-air-gap cylindrical dielectric barrier discharge’ model. The obtained results show that although the majority of ozone generators are of the volume discharge type, the novel volume discharge model has provided better results in terms of ozone generation and energy efficiency. A skid was built by using eight proposed generators and was successfully used for wastewater treatment.  相似文献   
84.
In this article, we exhaustively examined the effects of Mn substitution for Ni on the structures and electrochemical characterization of the CaNi5−xMnx (x = 0.2, 0.3, 0.5, 1) alloys prepared by mechanical synthesis for 40 hours at ball to powder weight ratio of 8:1. The characterization of electrodes was examined by X-ray diffraction, scanning electron microscope and electrochemical tests. In this context, the structural properties for each alloy have two major phases Ni, Ca2Ni7; Ni, CaNi3; Ni, CaNi5; Ni, CaNi3 where x = 0.2, 0.3, 0.5 and 1 respectively. The powder micrograph shows the existence of agglomerates has average particle size between 22 and 35 μm. In addition, the quantification by energy dispersive spectroscopy has been indicated the chemical composition of the all produced alloys is near their nominal composition. All electrodes are activated during the first cycle, independent of the Mn substitution rate. The highest values of discharge capacity and reversibility are obtained for x = 0.3 (125 mAh g−1, 0.17 V) and x = 0.5 (119 mAh g−1, 0.19 V) despite their low cycle stability. The evolution of DH/a2 ratio and the I0 exchange current density for the different Mn substitution rates is in accordance with that of the evolution of discharge capacities. The better kinetic properties is observed for x = 0.5 during electrochemical cycling.  相似文献   
85.
Prodrug technologies aimed at delivering nucleoside monophosphates into cells (protides) have proved to be effective in improving the therapeutic potential of antiviral and anticancer nucleosides. In these cases, the nucleoside monophosphates are delivered into the cell, where they may then be further converted (phosphorylated) to their active species. Herein, we describe one of these technologies developed in our laboratories, known as the phosphoramidate protide method. In this approach, the charges of the phosphate group are fully masked to provide efficient passive cell‐membrane penetration. Upon entering the cell, the masking groups are enzymatically cleaved to release the phosphorylated biomolecule. The application of this technology to various therapeutic nucleosides has resulted in improved antiviral and anticancer activities, and in some cases it has transformed inactive nucleosides to active ones. Additionally, the phosphoramidate technology has also been applied to numerous antiviral nucleoside phosphonates, and has resulted in at least three phosphoramidate‐based nucleotides progressing to clinical investigations. Furthermore, the phosphoramidate technology has been recently applied to sugars (mainly glucosamine) in order to improve their therapeutic potential. The development of the phosphoramidate technology, mechanism of action and the application of the technology to various monophosphorylated nucleosides and sugars will be reviewed.  相似文献   
86.
87.
The present work investigates, for the first time, the dry sliding friction and wear behaviour of fully dense, predominantly single-phase MoAlB ceramics against alumina (Al2O3) and 100Cr6 steel counterparts. Against Al2O3, the friction coefficient (μ) increased with increasing load and the wear was highly dependent on the load applied. A transition from mild wear under 1 N and 4 N to severe wear at 10 N occurred. Scanning electron microscopy revealed that abrasion is the dominant wear mechanism. Against steel, μ decreased with increasing load and the wear rates were low, under all applied loads. The morphologies of the worn surfaces against steel were characterized by the appearance of a rippled layers. Atomic force microscopy and Raman spectroscopy were used to propose a possible formation mechanism of such patterns. X-ray photoelectron spectroscopy revealed the rippled surfaces to be composed of Fe2O3 and a mixture of MoOx.  相似文献   
88.
The limited number of writers and genuine signatures constitutes the main problem for designing a robust Handwritten Signature Verification System (HSVS). We propose, in this paper, the use of One-Class Support Vector Machine (OC-SVM) based on writer-independent parameters, which takes into consideration only genuine signatures and when forgery signatures are lack as counterexamples for designing the HSVS. The OC-SVM is effective when large samples are available for providing an accurate classification. However, available handwritten signature samples are often reduced and therefore the OC-SVM generates an inaccurate training and the classification is not well performed. In order to reduce the misclassification, we propose a modification of decision function used in the OC-SVM by adjusting carefully the optimal threshold through combining different distances used into the OC-SVM kernel. Experimental results conducted on CEDAR and GPDS handwritten signature datasets show the effective use of the proposed system comparatively to the state of the art.  相似文献   
89.
Journal of Mechanical Science and Technology - In order to estimate the seismic demand by using the nonlinear static procedure, different approximate methods have been developed. One of the most...  相似文献   
90.
Fe—Ni alloy,as a widely applied ferromagnetic material,is synthesized using selective laser melting(SLM).The chemical compositions and microstructure of the SLM Fe—Ni alloy are characterized by X-ray diffraction(XRD), energy dispersive X-ray spectroscopy and scanning electron microscopy.It was found that the samples exhibited fine grains with homogenous distribution when a low laser scanning velocity was used.Moreover,the magnetic properties of the samples with different laser parameters are also measured.It shows that the SLM Fe—30%Ni alloy possesses a low coercivity and high saturation magnetization.It also can be obtained that SLM is an alternative faster method to prepare soft magnetic material with complex shapes.Moreover,the magnetic properties can be influenced by the laser parameters.  相似文献   
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