全文获取类型
收费全文 | 6177篇 |
免费 | 224篇 |
国内免费 | 13篇 |
学科分类
工业技术 | 6414篇 |
出版年
2023年 | 42篇 |
2022年 | 57篇 |
2021年 | 94篇 |
2020年 | 82篇 |
2019年 | 77篇 |
2018年 | 95篇 |
2017年 | 109篇 |
2016年 | 163篇 |
2015年 | 121篇 |
2014年 | 191篇 |
2013年 | 295篇 |
2012年 | 246篇 |
2011年 | 353篇 |
2010年 | 273篇 |
2009年 | 285篇 |
2008年 | 287篇 |
2007年 | 278篇 |
2006年 | 265篇 |
2005年 | 230篇 |
2004年 | 208篇 |
2003年 | 158篇 |
2002年 | 136篇 |
2001年 | 108篇 |
2000年 | 111篇 |
1999年 | 128篇 |
1998年 | 212篇 |
1997年 | 135篇 |
1996年 | 144篇 |
1995年 | 97篇 |
1994年 | 102篇 |
1993年 | 97篇 |
1992年 | 85篇 |
1991年 | 73篇 |
1990年 | 72篇 |
1989年 | 67篇 |
1988年 | 65篇 |
1987年 | 70篇 |
1986年 | 50篇 |
1985年 | 55篇 |
1984年 | 58篇 |
1983年 | 43篇 |
1982年 | 53篇 |
1981年 | 52篇 |
1980年 | 37篇 |
1979年 | 32篇 |
1978年 | 37篇 |
1977年 | 37篇 |
1976年 | 50篇 |
1975年 | 42篇 |
1973年 | 35篇 |
排序方式: 共有6414条查询结果,搜索用时 0 毫秒
1.
Wolfgang Wendler 《电子产品世界》2006,(17):129-130
与美国同行争分夺秒抢占市场先机不同,欧洲测量仪器厂商Rohde&Schwarz公司的产品策略则相对稳健,他们的产品更专注于功能的多样化 相似文献
2.
Several variations of cache-based checkpointing for rollback error recovery from transient errors in shared-memory multiprocessors have been recently developed. By modifying the cache replacement policy, these techniques use the inherent redundancy in the memory hierarchy to periodically checkpoint the computation state. Three schemes, different in the manner in which they avoid rollback propagation, are evaluated in this paper. By simulation with address traces from parallel applications running on an Encore Multimax shared-memory multiprocessor, we evaluate the performance effect of integrating the recovery schemes in the cache coherence protocol. Our results indicate that the cache-based schemes can provide checkpointing capability with low performance overhead, but with uncontrollable high variability in the checkpoint interval 相似文献
3.
Ohne Zusammenfassung 相似文献
4.
Garey A. Fox John W. Fuchs Victor F. Medina Kaumudi Atapattu 《Canadian Metallurgical Quarterly》2007,133(3):255-262
Recent research has proposed the use of asphalt and tall-oil-pitch emulsions for stabilizing radioactive contamination deposited on surfaces in urban areas. The objective of this project was to investigate whether surface applied emulsions could capture airborne radioactive particulate. Laboratory experiments included wind-blown particulate capture studies using an acrylic column and particulate retainment experiments using a wind box capable of producing wind speeds of 96?km/h. A probe methodology was developed to relate particulate retainment to a tack force on the emulsion surface. Experiments were also performed to determine the potential for such emulsions to absorb particulate matter into their emulsion matrix. Tall-oil-pitch emulsions outperformed asphalt emulsions in terms of particulate retention, tack force, and the ability to absorb magnesium silicate. Both tall-oil-pitch and asphalt emulsions were capable of extracting 22–24?g?m?2 of powder from particulate-laden airflow. Tall-oil-pitch emulsions were capable of retaining as much as 5–10% of magnesium silicate powder applied (i.e., retainment densities of 10–20?g?m?2) even after seven?days of curing and after applying 96.5?km/h (60?mph) wind. Tall-oil-pitch emulsions were able to absorb surface-applied magnesium silicate (approximately 0.1–0.2?g of magnesium silicate per 1.0?g of emulsion within three?days) into their emulsion matrix, preventing the magnesium silicate from being exposed to the external environment. Initial results with these five different emulsion formulations suggested particulate capture was feasible. Future emulsion formulations (i.e., longer curing times with greater acid concentrations) should be tested to optimize this postdetonation response strategy. 相似文献
5.
6.
FD Fuchs 《Canadian Metallurgical Quarterly》1996,67(4):267-269
We have treated 50 patients with stage III, VI malignant tumors confirmed by pathology. The patients were divided into two groups. One group was treated by combination of chemotherapy and traditional Chinese medicine (treatment group); the other only by chemotherapy (control group). The effect of cancer treatment was evaluated according to the criteria of WHO. The results showed that the effective rate was 80% in treatment group and 52% in control group. The pain relieving rate was 68% in treatment group and 40% in control group (P < 0.01). This fact demonstrates that the application of traditional Chinese medicine can invigorate blood circulation, eliminate blood stasis, soften hardness and dissolve the mass, nourish blood and increase vigor. This kind of application can not only enhance the effect of cancer treatment but also increase the cancer pain relieving rate. 相似文献
7.
On the suitability of agricultural by-products for the manufacture of granular activated carbon 总被引:1,自引:0,他引:1
An investigation of several agricultural by-products revealed that their suitability for activated carbon production is not determined by general material-specific features (elemental composition) but by type-specific features. A coarse-cellular structure (as in wood), which is indicated by porosities of the raw materials higher than 35% is disadvantageous. A specific change in the properties of cokes (porosity, density, hardness) is possible by varying the conditions of pyrolysis. By rapid heating in the pyrolysis step, for instance, macroporous residues are produced. Temperature and burnoff have the greatest influence on the quality of the activated carbon during the activation step. Of the investigated materials, coconut shells yield granular activated carbon of the highest quality. The following order of suitability of raw materials for activated carbon production was established: coconut shells> peach stones> plum stones> hazelnut shells> walnut shells> cherry stones. 相似文献
8.
9.
Sven Beyer Christian Jacobi Daniel Kröning Dirk Leinenbach Wolfgang J. Paul 《International Journal on Software Tools for Technology Transfer (STTT)》2006,8(4-5):411-430
In the verified architecture microprocessor (VAMP) project we have designed, functionally verified, and synthesized a processor
with full DLX instruction set, delayed branch, Tomasulo scheduler, maskable nested precise interrupts, pipelined fully IEEE
compatible dual precision floating point unit with variable latency, and separate instruction and data caches. The verification
has been carried out in the theorem proving system PVS. The processor has been implemented on a Xilinx FPGA.
A shorter version of this article with the title “Instantiating uninterpreted functional units and memory system: functional
verification of the VAMP” appeared in [8]. The work reported here was done while all the authors were with Saarland University. 相似文献
10.