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91.
A numerical calculation method based on the angle in a triple junction composed of a random grain boundary is proposed to predict the connectivity and stability of a grain boundary in a B10 copper-nickel alloy. The grain-boundary connectivity and its effect on corrosion resistance are studied combining computer-aided analysis with electrochemical impedance testing. The results show that the prediction of corrosion resistance using a grain-boundary connectivity numerical method is consistent with immersion experimental results. The B10 alloy exhibited the best corrosion resistance after cold rolling with a 9% reduction rate. The relationship between the grain-boundary characteristics and corrosion resistance is well established using the numerical method to quantify the grain-boundary connectivity. A higher connective frequency and a low proportion of grain-boundary angles between 60° and 180° in the triple junction is detrimental to corrosion resistance of the B10 alloy.  相似文献   
92.
A study of novel composite-structured CoCrFeNi3Si, CoCrFe2Ni2Si and Co2CrFeNi2Si high-entropy alloys, synthesised by vacuum arc melting, is presented. The designing criteria for the formation of such alloys were based on the enthalpy of mixing and the valence electron concentration. X-ray diffraction analysis revealed that all the alloys were composed of face-centered cubic and intermetallic phases. Scanning electron microscopy, along with elemental analysis, indicated that the face-centered cubic phase mainly contains Co, Cr, Fe and Ni, whereas, the intermetallic compound is Ni-Si rich. All the synthesised high-entropy alloys in the present investigation possess excellent compressive strength along with ductility at room temperature, suggesting significant potential application in the engineering field. Furthermore, enhanced hardness, wear resistance and corrosion resistance were achieved in all the designed high-entropy alloys. The previously given design parameters for the composite-structured high-entropy alloys are in good accord with the current research work.  相似文献   
93.
Mg–Sn-based alloys are considered as a promising precipitation-hardening system for applications at elevated temperatures, but the hardening effect is not satisfactory owing to sluggish nucleation and rapid coarsening of the major Mg2Sn lath precipitates. In this study, Cu and Al are added to a Mg–6Sn–1Mn base alloy. The age-hardening response and the microstructures of these modified alloys have been investigated and are compared to that of the base alloy. The additional elements are found to bring several beneficial effects to the alloys for applications at elevated temperatures. Firstly, a eutectic structure consisting of strong intermetallic phases, i.e. Mg2Cu in the Mg–6Sn–1Mn–2Cu alloy and Al0.93Cu1.07Mg in the Mg–6Sn–1Mn–2Cu–2Al alloy, remains stable along the grain boundaries after solution and ageing heat treatments. Secondly, the precipitate density has been increased significantly and the precipitate size has been refined remarkably during ageing at 200?°C. Moreover, the growth of the precipitates is inhibited remarkably during the over-ageing period. Therefore, the age-hardening response and over-ageing resistance are notably improved.  相似文献   
94.
There is a shortage of intervention strategies for children with behavior disorders which incorporate both home and school influences. To address this need, a service delivery model was evaluated for public school children (Pre-K through G2) who were at risk for educational failure on account of behavior problems, family dysfunction, and poverty and social disadvantage. Interventions based on eco-behavioral principles were delivered by home-visitors in consultation with clinical child psychologists. A primary goal of all treatment plans was to enhance parent-teacher communication. Children in the experimental group (N = 34) showed overall improvement (as judged by parents) and decreases in targeted problems (as reported by teachers and parents), relative to control students (N = 15). The program decreased the number of children placed in special education. There was indication that better communication between home and school related to academic improvement. The protocol provides a possible behavioral consultation model of early intervention for behavior disorders and demonstrates how clinical services can be integrated with systems-wide dropout prevention efforts.  相似文献   
95.
Intimate partner violence (IPV) theory often locates violence equitably between women and men. Women, however, sustain greater degrees of injury than men and often use violence as a measure of protection rather than as an act of aggression. Yet measures of protection must be viewed in multiple contexts. In this case, the context is poverty, which reveals that violence by women in response to IPV is not the only way that women deal with the violence in their lives. This article explicates four strategies that battered women in poverty deploy in their protective trajectory and highlight alternative resistance strategies women use to overcome multiple structural barriers.  相似文献   
96.
97.
Resistance and ambivalence about change are increasingly recognized as important determinants of treatment outcomes. Moreover, resistance and ambivalence are thought to be theoretically related in that clients who are more ambivalent about change are more likely to demonstrate resistance to the process and tasks of treatment. In the context of cognitive behavioural therapy (CBT) for generalized anxiety disorder, the present study simultaneously examined early resistance and ambivalence using two observer-based coding systems in order to determine their inter-relationship and, importantly, to investigate their relative contributions to outcome. Resistance was also coded during mid-treatment in order to investigate possible mediation pathways. Early ambivalence (clients’ arguments against change or counter-change talk) was found to be no longer related to outcomes when early resistance was taken into account, suggesting that disharmony in the therapeutic relationship is more important to outcomes than ambivalence per se. Moreover, mid-treatment resistance partially mediated the relationship between early resistance and post-treatment worry severity. That is, higher early opposition to therapist direction is related to poorer outcomes, in part because it is associated with greater resistance during the working phase of CBT. The findings underscore the critical need for therapists to be sensitive to identifying resistance early and throughout treatment.  相似文献   
98.
Privacy is psychologically important, vital for democracy, and in the era of ubiquitous and mobile surveillance technology, facing increasingly complex threats and challenges. Yet surveillance is often justified under a trope that one has ‘nothing to hide’. We conducted focus groups (N = 42) on topics of surveillance and privacy and using discursive analysis, identify the ideological assumptions and the positions that people adopt to make sense of their participation in a surveillance society. We find a premise that surveillance is increasingly inescapable, but this was only objected to when people reported feeling misrepresented, or where they had an inability to withhold aspects of their identities. The (in)visibility of the surveillance technology also complicated how surveillance is constructed. Those interested in engaging the public in debates about surveillance may be better served by highlighting the identity consequences of surveillance, rather than constructing surveillance as a generalised privacy threat.  相似文献   
99.
Our contribution deals with the emotional and cognitive foundations of resistance to persuasive information. We rely on an original quasi‐experimental protocol that simulates the flow of information and the respondents' reactions to persuasive arguments on global climate change. Respondents in a representative sample (N = 604) were asked if they supported reduction of economic activity to reduce climate warming and were then provided, based on their support or disapproval for this first argument, with counterattitudinal arguments to test their resistance to persuasion. This article highlights that sophistication strengthens resistance to persuasion, whereas anxiety has a double effect: directly, it decreases resistance; indirectly, it interacts with political sophistication and makes sophisticates less likely to resist persuasion when facing arguments inconsistent with their previous beliefs. Nonanxious citizens, in turn, are more likely to resist persuasion when their political sophistication increases. We also provide evidence that the joint effect of anxiety and sophistication is moderated by the ideological identification of respondents.  相似文献   
100.
致病性微生物耐药性严重化是一道世界性医学难题。微生物使出种种耐药的"招术",不只是其对药物作用的反应,更应看到是耐药内外因相互作用的结果,是其生物本性之使然。微生物的基本特性使其具备这种"能耐"。这些耐药性应存在一定的"原动机制",可以认定微生物的耐药性必然永远存在。人类社会必须构建长效的、与时俱进的防、抗致病微生物耐药性的卫生工作机制。  相似文献   
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