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排序方式: 共有141条查询结果,搜索用时 15 毫秒
81.
Melanoma differentiation associated gene-7/interleukin-24 (MDA-7/IL-24), a secreted protein of the IL-10 family, was first identified more than two decades ago as a novel gene differentially expressed in terminally differentiating human metastatic melanoma cells. MDA-7/IL-24 functions as a potent tumor suppressor exerting a diverse array of functions including the inhibition of tumor growth, invasion, angiogenesis, and metastasis, and induction of potent “bystander” antitumor activity and synergy with conventional cancer therapeutics. MDA-7/IL-24 induces cancer-specific cell death through apoptosis or toxic autophagy, which was initially established in vitro and in preclinical animal models in vivo and later in a Phase I clinical trial in patients with advanced cancers. This review summarizes the history and our current understanding of the molecular/biological mechanisms of MDA-7/IL-24 action rendering it a potent cancer suppressor.  相似文献   
82.
Journal of Computational Electronics - This paper presents a numerical study of highly dispersive optical solitons that maintain a cubic–quintic–septic nonlinear (also know as...  相似文献   
83.
Journal of Materials Science - Ever since its discovery ultrafast demagnetization has remained one of the most intriguing research areas in magnetism. Here, we demonstrate that in [Co (tCo)/Pd...  相似文献   
84.
The present paper describes the development of a low cost, microcontroller-based variable voltage variable frequency sinusoidal power source, which is the demand of the day for various applications. The power source is developed using MOSFET H-bridge inverter and with a stand alone LCD display system. The design methodology proposes to utilize a novel concept of generating sinusoidal pulse width modulation signals for the driver circuit of the inverter. The system proposes to incorporate a ROM-based LUT within the power source itself for the sinusoidal signal generation with enhanced stability. This low cost, yet accurate power source has been successfully developed for wide range of voltage commands (30-80 V rms) and frequency commands (40-70 Hz), and their real-life performances in voltage wave generation were also found to be quite satisfactory.  相似文献   
85.
The leader node in a distributed computing system is responsible to establish coordination among all other nodes that are situated apart geographically. Selection of a suitable leader is one of the major and challenging problems. In this paper, a novel leader election algorithm is proposed based on resources of each node in a ring network. All the nodes compute resource strength values by considering available resources like CPU, memory capacity, and residual energy. A node with the highest resource strength over the network is elected as the leader. The proposed algorithm has also considered sudden failure of the nodes particularly when it is the leader node. Moreover, addition of new nodes is also considered. The proposed algorithm shows improvement on message complexity over the network and resource‐based priority generation, which helps in efficient election of the leader. To validate, the proposed algorithm is extensively simulated as well as real‐life hardware experiment is also done. In the experiment, 2 cases are considered with different weight of the resources, and consequent effects are shown. The results are also compared with the existing algorithms, and it is observed that the proposed work comparably performs better that the existing related algorithms.  相似文献   
86.
Cultivars with efficient root systems play a major role in enhancing resource use efficiency, particularly water absorption, and thus in drought tolerance. In this study, a diverse wheat association panel of 136 wheat accessions including mini core subset was genotyped using Axiom 35k Breeders’ Array to identify genomic regions associated with seedling stage root architecture and shoot traits using multi-locus genome-wide association studies (ML-GWAS). The association panel revealed a wide variation of 1.5- to 50-fold and were grouped into six clusters based on 15 traits. Six different ML-GWAS models revealed 456 significant quantitative trait nucleotides (QTNs) for various traits with phenotypic variance in the range of 0.12–38.60%. Of these, 87 QTNs were repeatedly detected by two or more models and were considered reliable genomic regions for the respective traits. Among these QTNs, eleven were associated with average diameter and nine each for second order lateral root number (SOLRN), root volume (RV) and root length density (RLD). A total of eleven genomic regions were pleiotropic and each controlled two or three traits. Some important candidate genes such as Formin homology 1, Ubiquitin-like domain superfamily and ATP-dependent 6-phosphofructokinase were identified from the associated genomic regions. The genomic regions/genes identified in this study could potentially be targeted for improving root traits and drought tolerance in wheat.  相似文献   
87.
What are the neural correlates of attractiveness? Using functional MRI (fMRI), the authors addressed this question in the specific context of the apprehension of faces. When subjects judged facial beauty explicitly, neural activity in a widely distributed network involving the ventral occipital, anterior insular, dorsal posterior parietal, inferior dorsolateral, and medial prefrontal cortices correlated parametrically with the degree of facial attractiveness. When subjects were not attending explicitly to attractiveness, but rather were judging facial identity, the ventral occipital region remained responsive to facial beauty. The authors propose that this region, which includes the fusiform face area (FFA), the lateral occipital cortex (LOC), and medially adjacent regions, is activated automatically by beauty and may serve as a neural trigger for pervasive effects of attractiveness in social interactions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
88.
India has fairly substantial resources of vanadium and only small reserves of niobium and tantalum. Vanadium occurs in the vast deposits of titaniferrous magnetite located in Bihar Orissa and Karnataka. It is also occurring as a minor constituent in most of the bauxite deposits in the country. Niobium and tantalum occurs as niobium-tantalite in pegmatite deposits in mica mining belts of Bihar and Rajasthan. This mineral is also found in the cassiterite deposits of Baster in Madhya Pradesh.

This paper presents an overview of the development work carried out at Bhabha Atomic Research Centre on the process metallurgy of these three Group V metals starting from their indigenous resources. The coverage includes separation of pure individual elements, preparation of pure intermediates, techniques of reduction to metal and final purification.  相似文献   
89.
A combined experimental and numerical study has been conducted to investigate the occurrence of off-stagnation peak for laminar methane/air flame impinging on a flat surface. Experiments were conducted for three tube burners of internal diameter 8 mm, 9.7 mm and 12 mm. Radial heat flux distributions were compared (experimentally) for different burner diameters under identical operating conditions (with firing rates of 0.25 kW, 0.40 kW and 0.50 kW, ? = 1 and H = 40 mm). An off-stagnation point peak in heat flux was observed for some of the configurations in the present study which is in accordance with the previous findings. This off-stagnation point peak is a function of stand-off distance between the exit plane of the burner and the plate and also the distance between flame-tip and the plate. A satisfactory explanation is presented to explain the existence of this off-stagnation peak with the help of results of numerical simulation carried out with commercial CFD code FLUENT. It is concluded that this off-stagnation peak in heat flux is primarily due to the peak in the axial velocity profile close to the impingement surface.  相似文献   
90.
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