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1.
This study describes two novel bacteriophages infecting members of the Bacillus pumilus group. Even though members of the group are not recognized as pathogenic, several strains belonging to the group have been reported to cause infectious diseases in plants, animals and humans. Bacillus pumilus group species are highly resistant to ultraviolet radiation and capable of forming biofilms, which complicates their eradication. Bacteriophages Novomoskovsk and Bolokhovo were isolated from soil samples. Genome sequencing and phylogenetic analysis revealed that the phages represent two new species of the genus Andromedavirus (class Caudoviricetes). The phages remained stable in a wide range of temperatures and pH values. A host range test showed that the phages specifically infect various strains of B. pumilus. The phages form clear plaques surrounded by halos. Both phages Novomoskovsk and Bolokhovo encode proteins with pectin lyase domains—Putative depolymerases. Obtained in a purified recombinant form, the proteins produced lysis zones on the lawn of a B. pumilus strain. This suggests that Novomoskovsk and Bolokhovo may be effective for the eradication of B. pumilus biofilms.  相似文献   
2.
Anionic polymerization of ε‐caprolactam was performed in the presence of only 5 wt % of aromatic polyimides having five‐ and six‐membered imide cycles and bearing hexafluoroisopropylidene, ether, fluorene, siloxane, phthalide, or SO3H? groups, both in the polymer backbone and as side moieties. The synthesized new copolymers were fully characterized by IR spectroscopy, thermomechanical analysis, dilatometry, and X‐ray diffraction. Tough and frictional properties of the obtained copolymers were estimated as well. It was found that on the selection of polyimide activator it is possible to gain the desirable control over the polymer properties, namely the gel‐fraction content, phase composition, compression modulus, notched Izod impact strength, temperature of frictional contact, friction coefficient, etc. These investigations will facilitate the choice of the optimum macromolecular activator for the modification of both the synthetic method and the properties of the commercial polycaproamide. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   
3.
Field coupling in electric-current-carrying composites is studied. Governing equations describing electromagnetic, thermal, and mechanical field interactions in anisotropic materials and a corresponding two-dimensional approximation for transversely isotropic plates are discussed. A problem of electric current?Cinduced heating and the associated thermal stresses in the electrified carbon fiber polymer matrix composite plate is considered. A closed-form solution for the temperature distribution is obtained. It is shown that application of the electric current leads to a significant temperature gradient across the plate. This, in turn, results in a considerable rise of the in-plane compressive stresses in the direction transverse to the direction of the applied current.  相似文献   
4.
5.
A computational technique based on Maxwell's methodology is presented for evaluating the effective thermal conductivity of isotropic materials with periodic or random arrangement of spherical pores. The basic idea of the approach is to construct an equivalent sphere in an infinite space whose effects on the temperature at distant points are the same as those of a finite cluster of spherical pores arranged in a pattern representative of the material in question. The thermal properties of the equivalent sphere then define the effective thermal properties of the material. This procedure is based on a semi-analytical solution of a problem of an infinite space containing a cluster of non-overlapping spherical pores under prescribed temperature gradient at infinity. The method works equally well for periodic and random arrays of spherical pores.  相似文献   
6.
Today, the Internet of Things (IoT) becomes a heterogeneous and highly distributed structure which can respond to the daily needs of people and different organizations. With the fast development of IT‐based technologies such as IoT and cloud computing, low‐cost health services and their support, efficient supervision of the centralized management, and monitoring of public health can be realized. Therefore, there has been increasing attention in the integration of IoT and health care both in academic and the business world. However, while the health care service industry fully holds the welfares of information systems for its personnel and patients, there is a need for an improved understanding of the issues and opportunities related to IoT‐based health care systems. But, as far as we know, the detailed review and deep discussion in this field are very rare. Hence, in this paper, we presented a literature review on the IoT‐based health care services from papers published until 2018. Moreover, the drawbacks and benefits of the reviewed mechanisms have been discussed, and the main challenges of these mechanisms are highlighted for developing more efficient IoT techniques over health care services in the future. The results of this paper will be valuable for both practitioners and academicians, and it can provide visions into future research areas in this domain. By providing comparative information and analyzing the current developments in this area, this paper will directly support academics and working professionals for better knowing the progress in IoT mechanisms. As a general result, we found that IoT could help the governments to improve health services in society and commercial interactions.  相似文献   
7.
The sulfated polysaccharides from brown algae – the fucoidans – are known to be a topic of numerous studies, due to their beneficial biological activities including anti-tumour activity. In this study the effect of fucoidans isolated from brown algae Saccharina cichorioides, Fucus evanescens, and Undaria pinnatifida on the proliferation, neoplastic transformation, and colony formation of mouse epidermal cells JB6 Cl41, human colon cancer DLD-1, breast cancer T-47D, and melanoma RPMI-7951 cell lines was investigated. The algal fucoidans specifically and markedly suppressed the proliferation of human cancer cells with less cytotoxic effects against normal mouse epidermal cells. The highly sulfated (1 → 3)-α-l-fucan from S. cichorioides was found to be vitally important in the inhibition of EGF-induced neoplastic transformation of JB6 Cl41 cells. In colony formation assay the fucoidans from different species of brown algae showed selective anti-tumour activity against different types of cancer, which depended on unique structures of the investigated polysaccharides. These results provide evidence for further exploring the use of the fucoidans from S. cichorioides, F. evanescens, and U. pinnatifida as novel chemotherapeutics against different types of cancer.  相似文献   
8.
In this paper, the electric fields in the wind turbine blades due to the lightning stepped leader are studied, and the dielectric breakdown is assessed. The developed finite element analysis (FEA) includes the full length of the leader and enables one to incorporate various uniform and non‐uniform charge density models. The lightning striking distance is calculated using the rolling sphere method. The electric field in a horizontal axis wind turbine with three blades representing Sandia 100 m All‐glass Baseline Wind Turbine Blades (SNL 100‐00) at three different lightning protection levels (LPL) is computed and compared to the dielectric breakdown strength of the blades. The dielectric breakdown strength of the blades is evaluated based on the experimental data. The results show that the tip region of the blade is the most vulnerable to the dielectric breakdown with the safety factor as low as 1.32 at LPL I. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
9.
Misattributions people make about their own affective reactions can be used to measure attitudes implicitly. Combining the logic of projective tests with advances in priming research, the affect misattribution procedure (AMP) was sensitive to normatively favorable and unfavorable evaluations (Experiments 1-4), and the misattribution effect was strong at both fast and slow presentation rates (Experiments 3 and 4). Providing further evidence of validity, the AMP was strongly related to individual differences in self-reported political attitudes and voting intentions (Experiment 5). In the socially sensitive domain of racial attitudes, the AMP showed in-group bias for Black and White participants. AMP performance correlated with explicit racial attitudes, a relationship that was moderated by motivations to control prejudice (Experiment 6). Across studies, the task was unaffected by direct warnings to avoid bias. Advantages of the AMP include large effect sizes, high reliability, ease of use, and resistance to correction attempts. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
10.
Antiarrhythmic effects of melatonin have been demonstrated ex vivo and in rodent models, but its action in a clinically relevant large mammalian model remains largely unknown. Objectives of the present study were to evaluate electrophysiological and antiarrhythmic effects of melatonin in a porcine model of acute myocardial infarction. Myocardial ischemia was induced by 40-min coronary occlusion in 25 anesthetized pigs. After ischemia onset, 12 animals received melatonin (4 mg/kg). 48 intramyocardial electrograms were recorded from left ventricular wall and interventricular septum (IVS). In each lead, activation time (AT) and repolarization time (RT) were determined. During ischemia, ATs and dispersion of repolarization (DOR = RTmax − RTmin) increased reaching maximal values by 3–5 and 20–25 min, respectively. Ventricular fibrillation (VF) incidence demonstrated no relations to redox state markers and was associated with increased DOR and delayed ATs (specifically, in an IVS base, an area adjacent to the ischemic zone) (p = 0.031). Melatonin prevented AT increase in the IVS base, (p < 0.001) precluding development of early VF (1–5 min, p = 0.016). VF occurrence in the delayed phase (17–40 min) where DOR was maximal was not modified by melatonin. Thus, melatonin-related enhancement of activation prevented development of early VF in the myocardial infarction model.  相似文献   
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