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991.
992.
Yufang Cheng 《Computers in human behavior》2011,27(1):576-584
In order to understand whether a 3D virtual learning environment is effective in facilitating students’ application ability, we designed a 3D virtual supermarket (3DVS) to help business students to transform abstract class theory into concrete application ability in the real world. In the 3DVS, a virtual customer poses questions to the participant, and then the participant, as a simulated clerk, has to reply to the questions. All of the questions in the 3DVS were developed from marketing mix theory and given a scenario-based form. To understand the effects of the 3DVS, the participants were randomly divided into control group (CG) and experiment group (EG), and only the EG participants were trained with the 3DVS. After examined by pretest and posttest, the results of posttest indicated that the participants of the EG performed significantly better in terms of knowledge application than did those of the CG. 相似文献
993.
The interactive whiteboard (IWB) has become a popular technology for instructors over the last decade. Though research asserts that the IWBs facilitate learning in different ways, there is a lack of studies examining actual IWB use in classroom settings based on learners’ perspectives by means of valid instruments. The purpose of this study is to develop a valid and reliable interactive whiteboard student survey in order to evaluate the IWB use based on perceptions of students who have been taught with IWBs. In establishing the theoretical base of the survey, the Technology Acceptance Model (TAM) and constructivist learning theories were considered. In addition, with respect to IWB use in classrooms, a number of studies emanated from countries such as the UK, the USA, and Australia were examined, and similar research questionnaires and findings and also reflections of students about IWBs were utilized to create an item pool. A 39-item survey was conducted among middle school students (N = 263) from the city of Istanbul in Turkey. Collected data was exposed to exploratory factor analysis and resulted in a 26-item, three-factor survey, whose factors were named as the perceived efficiency of IWB, perceived learning contribution and motivation, and the perceived negative effects of IWB. The results of the analyses illustrated that this new IWB student scale, which explains 50% of the total variance with a good level of Cronbach’s Alpha coefficient (0.93) is a valid and reliable instrument designed specifically for measuring the use of IWBs in real classroom settings. Besides, theoretical foundations of interactive whiteboard use, the development process of the instrument, and results of validity and reliability analyses were discussed in detail. 相似文献
994.
Students learn new instructions well by building on relevant prior knowledge, as it affects how instructors and students interact with the learning materials. Moreover, studies have found that good prior knowledge can enable students to attain better learning motivation, comprehension, and performance. This suggests it is important to assist students in obtaining the relevant prior knowledge, as this can enable them to engage meaningfully with the learning materials. Tests are often used to help instructors assess students’ prior knowledge. Nevertheless, conventional testing approaches usually assign only a score to each student, and this may mean that students are unable to realize their own individual weaknesses. To address this problem, instructors can diagnose the test results to provide more detailed information to each student, but this is obviously a time-consuming process. Therefore, this study proposes a testing-based diagnosis system to assist instructors and students in diagnosing and strengthening prior knowledge before new instruction is undertaken. Furthermore, an experiment was conducted to evaluate the effectiveness of the proposed approach in an interdisciplinary course, since several studies have indicated that students learn more and better in such courses when applying relevant prior knowledge to what they are learning. The experimental results show that the developed system is able to effectively diagnose students’ prior knowledge and enhance their learning motivation and performance on an interdisciplinary course. In addition, two diagnostic evaluations were also conducted to assess whether the diagnoses given by the system were consistent with the decisions of experts. The results demonstrate that the proposed system can effectively assist instructors and students in diagnosing and strengthening prior knowledge before new instruction is undertaken, since the diagnoses produced by the system were broadly consistent with those of experts. 相似文献
995.
Jiarui HuangAuthor Vitae Youjie WuAuthor VitaeCuiping GuAuthor Vitae Muheng ZhaiAuthor VitaeYufeng SunAuthor Vitae Jinhuai LiuAuthor Vitae 《Sensors and actuators. B, Chemical》2011,155(1):126-133
Hierarchically three-dimensional (3D) porous ZnO architectures are synthesized by a template-free, economical aqueous solution method combined with subsequent calcination. First, the precursors of interlaced and monodisperse basic zinc nitrate (BZN) nanosheets are prepared. Then calcination of the precursors produces hierarchically 3D porous ZnO architectures composed of interlaced ZnO nanosheets with high porosity resulting from the thermal decomposition of the precursors. The products are characterized by X-ray diffraction, thermogravimetric-differential thermalgravimetric analysis, scanning electron microscopy, transmission electron microscopy, and Brunauer-Emmett-Teller N2 adsorption-desorption analyses. The BET surface area of the hierarchically porous ZnO nanostructures was calculated to be 12.8 m2 g−1. Compared with ZnO rods, the as-prepared porous ZnO nanosheets exhibit a good response and reversibility to some organic gases, such as ethanol and acetone. The responses to 100 ppm ethanol and acetone are 24.3 and 31.6, respectively, at a working temperature of 320 °C. These results show that the porous ZnO architectures are highly promising for gas sensor applications, as the gas diffusion and mass transportation in sensing materials are significantly enhanced by their unique structures. Moreover, it is believed that this solution-based approach can be extended to fabricate other porous metal oxide materials with a unique morphology or shape. 相似文献
996.
997.
在多媒体教学过程中,教师容易受限于讲台,分发教学资料时学生轮流使用移动存储设备连接教学设备,效率低下,并且容易使某些病毒相互传播.为了保证教学质量,改善教辅工具,在分析了蓝牙无线技术、J2ME技术等相关技术的基础上,利用配备蓝牙模块的智能手机制作无线教辅工具,使用蓝牙手机无线控制PPT文件播放和无线批量传输文件.重点阐述了基于J2ME蓝牙无线技术的软件设计方案、实现中的关键问题和相应的解决办法,并进行了原型系统实验.实验结果表明:设计的软件不需要投入过多的成本便可实现移动手机控制多媒体教学,具有较高的应用价值. 相似文献
998.
999.
This paper presents a study carried out at the University of the Basque Country UPV/EHU with the aim of evaluating the CM-ED (concept map editor) with social education students. Concept mapping is a widely accepted technique that promotes meaningful learning. Graphically representing concepts of the learning domain and relationships between them helps students integrate new knowledge into their current cognitive structure. Due to the flexibility of computer-aided drawing graphs, several concept mapping tools have been developed and their use has been studied over the last few years. CM-ED is a multilingual and multimedia software program designed for drawing concept maps. Until recently, CM-ED had been mainly used and evaluated in computer science university degree. This paper represents a qualitative step in the evaluation of CM-ED: from technical students to students of more theoretical fields. The main characteristics of the CM-ED editor and the carried out study are presented in this paper. 相似文献
1000.
Information retention from PowerPoint and traditional lectures 总被引:1,自引:0,他引:1
The benefit of PowerPoint™ is continuously debated, but both supporters and detractors have insufficient empirical evidence. Its use in university lectures has influenced investigations of PowerPoint’s effects on student performance (e.g., overall quiz/exam scores) in comparison to lectures based on overhead projectors, traditional lectures (e.g., “chalk-and-talk”), and online lectures. Thus far, comparisons of overall exam scores have yielded mixed results. The present study decomposes overall quiz scores into auditory, graphic, and alphanumeric scores to reveal new insights into effects of PowerPoint presentations on student performance. Analyses considered retention of lecture information presented to students without the presence of PowerPoint (i.e., traditional lecture), auditory information in the presence of PowerPoint, and visual (i.e., graphic and alphanumeric) information displayed on PowerPoint slides. Data were collected from 62 students via quiz and questionnaire. Students retained 15% less information delivered verbally by the lecturer during PowerPoint presentations, but they preferred PowerPoint presentations over traditional presentations. 相似文献