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41.
Conventional copper chemical mechanical planarization (CMP) techniques are being pushed to their limits by increasing industrial standards caused by device miniaturization and the use of new materials. There is a need to investigate alternative methods of polishing to maintain and/or improve planarization standards while operating at low downforce. In this study, electrochemical mechanical planarization (ECMP) is considered as an alternative and/or an extension to current CMP processes. ECMP is unique due to the combination of an applied voltage to oxidize Cu and an abrasion from a polishing pad, which potentially allows the system to achieve high levels of planarization through the use of an appropriately tailored electrolyte. An electrolyte containing 1.0 M potassium phosphate salt concentration with a pH value of 2 and a benzotriazole (BTA) concentration of 0.001 M was tested for its planarization capability on patterned Cu structures using a custom built ECMP tool. Feature sizes of the Cu structures were varied from 1 to 6 μm. Similar planarization results were achieved using three pad types. All experiments were performed at 0.5 V versus Ag/AgCl reference. The average step height reduction (SHR) was ~840 nm while the decrease in the average metal thickness removed (λavg) was on the order of ~430 nm. Because features were approximately 50% of the substrate area, the total average metal thickness removed was approximately half of the SHR for all three pad types.  相似文献   
42.
The present investigation examined whether daily smokers with posttraumatic stress disorder (PTSD), as compared to daily smokers with either anxiety psychopathology or no current Axis I psychopathology, have decreased success in the early phases of a self-guided smoking quit attempt. Participants were 140 daily smokers (81 women; M (age) = 29.5; SD = 11.9; range = 18-65 years); approximately one-third of the sample met criteria for current PTSD (n = 47), one-third met criteria for other current anxiety disorders (without PTSD; n = 33), and one-third did not meet criteria for any current Axis I disorder (n = 60). Consistent with prediction, membership in the PTSD group, compared to membership in the other anxiety disorders group and the group with no current Axis I psychopathology, was associated with increased risk of lapse during the first week following quit day. Additionally, daily smokers with PTSD and other anxiety disorders were at significantly increased risk of relapse during the first week post-cessation compared to persons without Axis I psychopathology. However, the PTSD group and the other anxiety disorders group did not differ from one another in terms of relapse. Results suggest that PTSD is associated with increased risk of smoking lapse and relapse compared to smokers with no current Axis I psychiatric problems, and increased risk of early smoking lapse but not relapse, as compared to those with other anxiety disorders. Findings provide novel evidence that PTSD, and perhaps anxiety disorders more generally, may be important factors in reducing the odds of successful unaided quit attempts in the early phases of cessation.  相似文献   
43.
Most empirically supported interventions for adolescent mental health problems are either downward adaptations of adult treatments or upward adaptations of child treatments. Although these treatments show respectable effects with teens, a review of the outcome research reveals significant gaps, both in coverage of adolescent conditions and problems (e.g., eating disorders, suicidality) and in attention to the biological, psychological, and social dimensions of adolescent development. The authors critique the field, propose a biopsychosocial framework for the development of dysfunction and intervention, and discuss ways the developmental literature can and cannot inform intervention and research. A long-term goal is an array of developmentally tailored treatments that are effective with clinically referred teens and an enriched understanding of when, how, and why the treatments work. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
44.
The authors compared the influence of text difficulty--reading-level matched or grade-level matched--on the growth of poor readers' reading ability over 18 weeks of 1-to-1 tutoring. Forty-six 3rd-5th graders, including 25 with disabilities, were assigned randomly to 1 of 2 tutoring approaches or a control condition. Significant differences favored tutored children. Between approaches, the only significant difference was oral reading fluency, which favored students who read material at their reading level. Students who began with lower fluency made stronger gains in text matched to reading level; students with higher fluency profited from both treatments. When the 3 groups were combined, fluency was the strongest contributor to reading comprehension outcomes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
45.
Although the study of police–civilian relations has recently entered the intergroup communication arena, there are no studies of actual interactions between these social categories. In part to rectify that stark omission and guided by communication accommodation theory, 313 randomly sampled video recordings from police cars on traffic stops in Cincinnati, Ohio were content analyzed. The study revealed 3 key differences as a function of the officers' and drivers' races: (a) Black drivers were more likely to experience extensive policing during the stop; (b) the communication quality of White drivers was, on average, more positive than that of the Black drivers; and (c) officers' communication behavior was more positive when the officer and driver were of the same race. These findings are consistent with public opinion data and their implications for theory are discussed.  相似文献   
46.
We consider the problem of minimizing maximum lateness in a job shop. A conceptually simple simulation based procedure described in a recent paper by Hodgson et al [1] is modified to provide improved schedules. Computational experimentation is provided to identify the conditions under which the approach is most viable, and to report the procedure's performance on known test problems.  相似文献   
47.
48.
[Correction Notice: An erratum for this article was reported in Vol 93(2) of Journal of Applied Psychology (see record 2008-02855-019). Figure 2 on p. 184 (Theoretical Contributions section) is missing information about the numbers of teams and statements for the two groups using particularlistic strategies. For the decreasing and consistently low performance/decreasing and consistently low satisfaction group, there were 14 teams and 40 statements; for the decreasing and consistently low performance/increasing and consistently high satisfaction group, there were 11 teams and 46 statements.] This article explores the linkages between strategies for managing different types of conflict and group performance and satisfaction. Results from a qualitative study of 57 autonomous teams suggest that groups that improve or maintain top performance over time share 3 conflict resolution tendencies: (a) focusing on the content of interpersonal interactions rather than delivery style, (b) explicitly discussing reasons behind any decisions reached in accepting and distributing work assignments, and (c) assigning work to members who have the relevant task expertise rather than assigning by other common means such as volunteering, default, or convenience. The authors' results also suggest that teams that are successful over time are likely to be both proactive in anticipating the need for conflict resolution and pluralistic in developing conflict resolution strategies that apply to all group members. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
49.
The flame retardancy mechanisms of three aryl phosphates, triphenyl phosphate (TPP), resorcinol bis(diphenyl phosphate) (RDP) and bisphenol A bis(diphenyl phosphate) (BDP), in a polycarbonate/acrylonitrile–butadiene–styrene (PC/ABS) blend are investigated and compared. Further, the influence of polytetrafluorethylene (PTFE) on viscosity and thermal decomposition is discussed in the systems PC/ABS and PC/ABS + BDP. Mechanisms are proposed based on the results of various methods. Thermogravimetric analysis, Fourier transform infrared spectroscopy and kinetics are used to study the pyrolysis. The fire behaviour is studied by means of cone calorimeter measurements at different heat fluxes and the flammability is specified by limiting oxygen index (LOI) and UL 94. Rheology measurements are used to illuminate the changed dripping behaviour due to PTFE. TPP shows only a gas phase action. RDP shows mainly a gas phase action and some condensed phase action. BDP shows a crucial condensed phase action in addition to a gas phase action. TPP and RDP are somewhat superior in terms of flammability (LOI), whereas BDP shows superior performance in forced flaming combustion (cone calorimeter). Synergistic effects between PTFE and BDP are found. Copyright © 2007 Society of Chemical Industry  相似文献   
50.
This paper discusses the development of continuous SiC fiber‐reinforced HfB2‐SiC composite laminates. A range of techniques, based on resin‐based precursors and slurries, for infiltrating porous SiC preforms with HfB2 powder were developed. While resin‐based precursors proved to be ineffective due to low HfB2 yield and poor adhesion, the slurry infiltration techniques were effective to varying degrees. The greatest pore filling and composite densities were achieved using pressure and vibration‐assisted pressure infiltration techniques. SiCf/HfB2‐SiC laminates were subsequently developed via lamination, cure and pyrolysis of fabrics using a HfB2‐loaded polymeric SiC precursor, followed by HfB2 slurry infiltration and preceramic polymer infiltration and pyrolysis (PIP). Repeated PIP processing, for 6–10 cycles, resulted in density increases, from the 3.03–3.22 g/cm3 range after HfB2 slurry infiltration, to 3.97–4.03 g/cm3 after PIP processing. Correspondingly, there was a decrease in open porosity from approximately 52% to less than 11%. The matrix consisted of discreet, lightly sintered HfB2 particles dispersed in SiC. The PIP SiC matrix was primarily nanocrystalline after 1300°C pyrolysis, but experienced grain growth with further heat treatment at 1600°C.  相似文献   
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