全文获取类型
收费全文 | 857篇 |
免费 | 23篇 |
专业分类
电工技术 | 21篇 |
综合类 | 3篇 |
化学工业 | 171篇 |
金属工艺 | 12篇 |
机械仪表 | 21篇 |
建筑科学 | 11篇 |
能源动力 | 29篇 |
轻工业 | 43篇 |
水利工程 | 4篇 |
无线电 | 122篇 |
一般工业技术 | 133篇 |
冶金工业 | 236篇 |
原子能技术 | 21篇 |
自动化技术 | 53篇 |
出版年
2023年 | 4篇 |
2022年 | 4篇 |
2021年 | 9篇 |
2020年 | 7篇 |
2019年 | 11篇 |
2018年 | 10篇 |
2017年 | 12篇 |
2016年 | 13篇 |
2015年 | 13篇 |
2014年 | 13篇 |
2013年 | 48篇 |
2012年 | 21篇 |
2011年 | 33篇 |
2010年 | 23篇 |
2009年 | 30篇 |
2008年 | 33篇 |
2007年 | 30篇 |
2006年 | 27篇 |
2005年 | 21篇 |
2004年 | 26篇 |
2003年 | 18篇 |
2002年 | 18篇 |
2001年 | 13篇 |
2000年 | 17篇 |
1999年 | 16篇 |
1998年 | 76篇 |
1997年 | 46篇 |
1996年 | 55篇 |
1995年 | 30篇 |
1994年 | 26篇 |
1993年 | 26篇 |
1992年 | 12篇 |
1991年 | 13篇 |
1990年 | 15篇 |
1989年 | 12篇 |
1988年 | 8篇 |
1987年 | 2篇 |
1986年 | 6篇 |
1985年 | 2篇 |
1984年 | 8篇 |
1983年 | 10篇 |
1982年 | 7篇 |
1981年 | 10篇 |
1980年 | 8篇 |
1979年 | 6篇 |
1977年 | 5篇 |
1976年 | 12篇 |
1973年 | 4篇 |
1971年 | 4篇 |
1967年 | 1篇 |
排序方式: 共有880条查询结果,搜索用时 46 毫秒
91.
Hara T. Fukuda K. Kanazawa K. Shibata N. Hosono K. Maejima H. Nakagawa M. Abe T. Kojima M. Fujiu M. Takeuchi Y. Amemiya K. Morooka M. Kamei T. Nasu H. Chi-Ming Wang Sakurai K. Tokiwa N. Waki H. Maruyama T. Yoshikawa S. Higashitani M. Pham T.D. Yupin Fong Watanabe T. 《Solid-State Circuits, IEEE Journal of》2006,41(1):161-169
An 8-Gb multi-level NAND Flash memory with 4-level programmed cells has been developed successfully. The cost-effective small chip has been fabricated in 70-nm CMOS technology. To decrease the chip size, a one-sided pad arrangement with compacted core architecture and a block address expansion scheme without block redundancy replacement have been introduced. With these methods, the chip size has been reduced to 146 mm/sup 2/, which is 4.9% smaller than the conventional chip. In terms of performance, the program throughput reaches 6 MB/s at 4-KB page operation, which is significantly faster than previously reported and very competitive with binary Flash memories. This high performance has been achieved by the combination of the multi-level cell (MLC) programming with write caches and with the program voltage compensation technique for neighboring select transistors. The read throughput reaches 60 MB/s using 16I/O configuration. 相似文献
92.
93.
At the National Metrology Institute of Japan (NMIJ), the triple point of neon was measured using an NMIJ sealed cell, NMIJ Ne-5, and a modular sealed-cell model, Ec2Ne, made by the Istituto Nazionale di Ricerca Metrologica (INRiM) in Italy, and the results were compared. The melting curves obtained with the NMIJ Ne-5 cell show narrow widths (0.1 mK) over a wide range of the inverse of the melted fraction (1/F) from 1/F = 1 to 1/F = 10, which is consistent with a previous report. On the other hand, the width of the melting curves obtained with the Ec2Ne cell is 0.15 mK from 1/F = 1 to 1/F = 10. The liquidus point T tp estimated by the melting curves from F ~ 0.35 to F ~ 0.85 using the NMIJ cell is 0.05 mK higher than that using the Ec2Ne cell. The difference does not agree with the results obtained in an assay of the isotopic concentration from samples of the original Ne sources. The origin of the discrepancy has not been clarified yet. 相似文献
94.
K. Nakada H. Chikahisa K. Kobayashi S. Sakurai 《Tunnelling and Underground Space Technology incorporating Trenchless Technology Research》1996,11(4):431-443
The Takayama Festival Float Art Museum, which is located in Takayama City in the Hida District of Gifu Prefecture, in central Japan, is the first large-scale rock cavern for public use in Japan. This paper outlines the project rationale, structural design, and construction of the museum. 相似文献
95.
H Kambara M Kinoshita M Nakagawa T Sakurai C Kawai 《Canadian Metallurgical Quarterly》1995,25(2):55-61
Clinical indicators and the incidence of sudden death among 1,000 consecutive patients (816 males and 184 females) with myocardial infarction were investigated between 1983 and 1987 after coronary arteriography. Twenty-four patients died suddenly during a study period of 3.3 +/- 2.0 yrs. The yearly incidence of sudden death calculated by the Kaplan-Meier method was 0.7%, nearly half of the incidence of cardiac death (1.5%/yr). Univariate analysis demonstrated statistically significant differences in the number of cases with coronary thrombolysis in the acute phase, degree of coronary artery stenosis, the frequency and degree of congestive heart failure and angina in the acute and chronic phase, the presence of serious post-infarction arrhythmia, ejection fraction, recurrent myocardial infarction, and administration of digitalis and diuretics. between the sudden-death group and the cardiac and other patient groups. There was also a tendency to higher frequency of history of diabetes mellitus, presence of acute mitral regurgitation, nitrates and nicorandil treatment, and coronary artery bypass graft in the sudden-death group. Multivariate analysis revealed that digitalis and nitrates treatment and left anterior descending artery involvement were major contributing factors. Re-infarction, left ventricular ejection fraction, and nicorandil therapy were not significant and minor contributing factors. The incidence of sudden death increased with digitalis therapy (Odds' ratio of 9.59), and left anterior descending artery disease, and decreased with nitrates (0.34). 相似文献
96.
97.
Splenic marginal zone lymphoma (SMZL) most commonly presents with splenomegaly and stage IV disease. To our knowledge, there have been only two reported cases of SMZL without associated splenomegaly; one was detected incidentally after a bicycle accident. This previously reported case represented an early-stage SMZL with monoclonality confirmed by immunohistochemistry. We report a case of early-stage SMZL detected incidentally following a motor vehicle accident; monoclonality was confirmed by polymerase chain reaction analysis of paraffin-embedded tissue owing to the inability of confirmation by immunohistochemical techniques. We describe our findings and emphasize the importance of recognizing early stages of SMZL in incidental splenectomies by polymerase chain reaction analysis of paraffin-embedded tissue. Frozen tissue is not generally available in such cases. 相似文献
98.
CNSs AND OTHER Master's-prepared nurses are usually expected to lead research utilization (RU) efforts in organizations, but they often feel unprepared to do so. In this article, the need for clinical RU is discussed and ideas for implementation, using an adaptation of the Conduct and Utilization of Research in Nursing model, are described. The RU process is applied to research about once-a-day temperatures in afebrile patients. To assist nurses who are implementing research-based practice, we list studies that were used for the practice change, summarize the research base on the topic, and offer an example of clinical use of practice guidelines. 相似文献
99.
H Sakurai N Mitsuhashi O Murata Y Kitamoto Y Saito M Hasegawa T Akimoto T Takahashi S Nasu H Niibe 《Canadian Metallurgical Quarterly》1998,41(5):1157-1162
PURPOSE: To assess the efficacy and toxicity of combined modality therapy with short intensive primary chemotherapy in the treatment of primary CNS lymphoma (PCL). METHODS AND MATERIALS: Prospective study of 31 nonimmunodeficient patients with PCL treated with initial chemotherapy (13 shortened MACOP-B; and 18 modified MACOP with high dose methotrexate) followed by radiotherapy (whole brain and a boost). Patients were aged 18-72 years (median 51 years). Eight patients had positive CSF cytology of which one had spinal meningeal disease; one patient had vitreous involvement. RESULTS: The overall complete response (CR) rate after chemotherapy and radiotherapy was 69% (95% Confidence Interval: 49-84%). At a median follow-up of 24 months (4 months to 10 years) median survival was 23 months and 5-year survival 34%. Age, sex, performance status, number of lesions, CSF cytology, and extent of surgery were not of prognostic significance for survival on univariate analysis. Eleven patients developed mucositis (Grade 3+) and 21 hematological toxicity (Grade 3+) with 22 septicemic episodes in 15 patients. Three patients developed dementia, one assumed to be treatment related, and two due to recurrent disease. CONCLUSION: The survival results of short intensive primary chemotherapy followed by radiotherapy are similar to the results of chemotherapy in Stage IV aggressive systemic non-Hodgkin's lymphoma, although the treatment was associated with high morbidity. The apparently favorable results when compared to radiotherapy alone may at least in part be due to selection of patients with good prognostic factors. To confirm the benefit of combined chemotherapy and radiotherapy over either of the two modalities alone requires evaluation in large prospective and ideally randomized studies. 相似文献
100.
S Murata A Kobayashi T Takeuchi H Nakajima A Yoshida Y Kurosawa S Miki T Mizoguchi T Sakurai A Kawatani 《Canadian Metallurgical Quarterly》1996,65(3):109-119
Argatroban has selective antithrombin activity and widely used for treatment of ASO. In this study we investigated vasodilating activity of Argatroban besides antithrombin activity in ASO patients. Three patients who have undergone F-P bypasses previously which were all occluded received 10 mg or 20 mg of Argatroban per day intravenously for 4 weeks. Skin temperature were measured before and after administration of Argatroban at the point of 1, 2, 4 weeks which increased 2.3-6.0 degrees C after administration of Argatroban. Subjective symptoms were also improved and these patients became to be able to walk 1.5-3.3 km. These patients were also given PGE, intravenously, however, temperature increase was less than 1.1 degrees C. These results showed that Argatroban has not only antithrombin activity but also significant vasodilating activity resulting in increase of skeletal muscle blood flow. 相似文献