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71.
杨兰 《韩山师范学院学报》2003,24(1):27-32
票号是19世纪中国历史上一个重要的金融组织,其中,最负盛名的是山西票号,它在没有政府监管的情况下,繁荣昌盛近一个世纪,后因战乱不断才逐渐倒闭并消失。山西票号的经营制度深谙委托代理之道,也就是今天在经济学界大行其道的激励理论,并形成了一套行之有效的激励机制。尽管时代和环境都发生了变化,激励问题是永恒的。山西票号的激励制度的启示对当代中国银行业监管效率的改进是有益的。 相似文献
72.
薛岚 《楚雄师范学院学报》2004,19(3):84-86,126
通过现代观念与传统观念的对比,结合本地中学对化学教师素质的要求,重点探讨了化学教学中科学方法与思维的培养。 相似文献
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75.
Chang Xin Zhang Chengyu Gao Lan Liu Xiao You Shengping Qi Wei Wang Kang Guo Xin Su Rongxin Lu Han He Zhimin 《天津大学学报(英文版)》2019,25(5):488-496
2,5-Furandicarboxylic acid(FDCA) is a potential biorenewable chemical for applications including plastics, polyamides, drugs, etc. The selective biosynthesis of FDCA from 5-hydroxymethylfurfural(HMF) by a specific enzyme poses a great challenge. In this study, we reported an efficient strategy to produce FDCA from HMF by the tandem biocatalysis of laccase(Cot A-TJ102@UIO-66-NH_2) and Novozym 435. For the first step, a nanoparticle metal–organic framework was synthesized as a carrier to immobilize Cot A-TJ102@UIO-66-NH_2, which was assigned for the production of 5-formyl-2-furancarboxylic acid(FFCA) and featured an enzyme loading of 255.54 mg/g, specific activity of 135.90 U/mg, and solid loading ratio of 99.65%. Under optimal conditions, an ideal FFCA yield of 98.5% was achieved, and the Cot A-TJ102@UIO-66-NH_2 presented a high recycling capacity after 10 cycles. For the second step, Novozym 435 was applied for the further conversion of FFCA into FDCA, presenting a high FDCA yield of 95.5% under the optimized conditions. Novozym 435 also exhibited a high recyclability after eight cycles. As a result, the tandem biocatalysis strategy provided a 94.2% FDCA yield from HMF, indicating its excellence as a method for FDCA production. 相似文献
76.
Objective: We aim to describe the environment iodine concentration in salt, water and soil along Zhejiang Province coast in the China foreland. It will be helpful for us to judge whether this area is insufficient in iodine and universal iodized salt is necessary or not. Methods: We collected iodized salt samples, drinking water samples (tap water in the towns, and well water or spring water in the villages), water samples from different sources (ditches, lakes, rivers) and soil samples through random sampling in June, 2005. Salt, water and soil iodine was detected by arsenic-cerium redox method. Statistical analysis was expressed as mean±SEMby Windows SPSS 13.0. Results: (1) The iodine concentration in salt was 27.9±4.33 mg/kg (n=108). (2) Seventy-five water samples were collected. The water iodine value was 0.6~84.8 μg/L (mean of 11.66 μg/L). The watershed along the Qiantang River has significantly higher iodine content than the water in Lin'an in mountain area (P<0.01). The iodine content and mean iodine content of tap water, well or spring water and natural water sources were 4.30±2.43 μg/L (n=34), 23.59±27.74 μg/L (n=19)and 12.72±10.72 μg/L (n=22) respectively. This indicated that among environmental water sources, the ditch iodine content was the highest with river water iodine being the lowest (P<0.01). (3) Soil iodine value was 0.11~2.93 mg/kg (mean of 1.32 mg/kg).Though there was no statistical difference of soil iodine in different districts (P=0.131), soil iodine content correlated positively with water iodine content. Conclusion: Iodine concentration in salt accords with national policy of adding iodine in salt. Foreland has more iodine in water than mountain area. The data reflected that water and soil iodine in foreland area was not high, which suggests universal iodized salt should be necessary. Environment iodine has relatively close association with pollution. 相似文献
77.
Thi Quynh Trang Nguyen 《Teachers and Teaching》2017,23(1):78-90
Gaining and saving face are very important in Vietnam as a mechanism of social control, including the professional behaviour of teachers. Interviews with 15 lecturers (aged 24–37) at a teacher training college in a Central Coast province of Vietnam illustrated the relationship between their concepts of face and their beliefs about good teaching. Most were still strongly influenced by traditional Confucian beliefs about the role and position of teachers, the nature of teachers’ knowledge and the relationship between teachers and students. On the other hand, some teachers also were aware of, and to a limited extent open to, more modern ideas that seemed to be related to broad social changes and reforms in approaches to teaching and learning in recent decades in Vietnam. The findings suggest that some teacher educators are uncertain about the value of traditional professional wisdom in the context of critical changes in society and in education. The research also suggests that the concepts of face and saving face are important for teachers’ sense of agency, and that Vietnamese educational authorities could increase the effectiveness of innovations in teacher education by paying attention to the influence of concepts of face on the teachers’ beliefs and behaviours. 相似文献
78.
网络三维虚拟实验系统的设计与实现 总被引:1,自引:1,他引:0
根据虚拟现实技术特性,结合代表性的案例,分析网络三维虚拟实验系统的基本构成框架。依据虚拟实验系统的开发流程,以化学虚拟实验《实验室制取气体》的开发为例,介绍了基于Virtools开发网络三维虚拟实验系统的方法和过程。最后,对网络三维虚拟实验系统的开发应用进行了总结与展望。 相似文献
79.
徐兰 《阜阳师范学院学报(社会科学版)》2001,(5):64-67
民主革命时期毛泽东反腐倡廉的思想主要包括:关于反腐倡廉的重要性、关于反腐倡廉的主要内容等,论述了毛泽东反腐倡廉思想的历史意义和对现实的启迪意义。 相似文献
80.
The tectonic stress patterns were determined by a fuzzy comprehensive assessment method. Data of in-situ survey and fault information were utilized in the method. First, by making pressure and tension in the directions of along-river, cross-river, shear clockwise, and shear counterclockwise , 26 types of tectonic stress patterns were presented. And the stress vector of each pattern was obtained with FE software by taking unit displacement as boundary load. Then, by taking the 26 types of tectonic stress patterns as index set and 3 main stresses as factor set and choosing various operators, comparison of directions of computational stress vector and survey stress vector was made and the most possible tectonic stress pattern was obtained. Taking the 26 types of tectonic stress patterns as index set and strike angle as factor set, comparison of relationships between formation of fault and tectonic stress was made,and the tectonic stress patterns were assessed with known fault information. By summarizing the above assessment results, the most impossible tectonic stress pattern was obtained . Finally an engineering case was quoted to validate that the method is more feasible and reliable than traditional empirical method. 相似文献