全文获取类型
收费全文 | 900篇 |
免费 | 30篇 |
国内免费 | 1篇 |
学科分类
工业技术 | 931篇 |
出版年
2023年 | 2篇 |
2021年 | 14篇 |
2020年 | 8篇 |
2019年 | 7篇 |
2018年 | 18篇 |
2017年 | 16篇 |
2016年 | 31篇 |
2015年 | 8篇 |
2014年 | 26篇 |
2013年 | 44篇 |
2012年 | 29篇 |
2011年 | 44篇 |
2010年 | 34篇 |
2009年 | 38篇 |
2008年 | 39篇 |
2007年 | 39篇 |
2006年 | 24篇 |
2005年 | 32篇 |
2004年 | 39篇 |
2003年 | 20篇 |
2002年 | 17篇 |
2001年 | 13篇 |
2000年 | 22篇 |
1999年 | 20篇 |
1998年 | 70篇 |
1997年 | 41篇 |
1996年 | 21篇 |
1995年 | 12篇 |
1994年 | 14篇 |
1993年 | 18篇 |
1992年 | 7篇 |
1991年 | 11篇 |
1990年 | 13篇 |
1989年 | 19篇 |
1988年 | 19篇 |
1987年 | 14篇 |
1986年 | 8篇 |
1985年 | 13篇 |
1984年 | 10篇 |
1983年 | 5篇 |
1982年 | 2篇 |
1981年 | 2篇 |
1980年 | 5篇 |
1979年 | 6篇 |
1978年 | 5篇 |
1977年 | 8篇 |
1976年 | 7篇 |
1975年 | 5篇 |
1974年 | 2篇 |
1973年 | 5篇 |
排序方式: 共有931条查询结果,搜索用时 140 毫秒
1.
Takauchi H. Tamura H. Matsubara S. Kibune M. Doi Y. Chiba T. Anbutsu H. Yamaguchi H. Mori T. Takatsu M. Gotoh K. Sakai T. Yamamura T. 《Solid-State Circuits, IEEE Journal of》2003,38(12):2094-2100
We describe a CMOS multichannel transceiver that transmits and receives 10 Gb/s per channel over balanced copper media. The transceiver consists of two identical 10-Gb/s modules. Each module operates off a single 1.2-V supply and has a single 5-GHz phase-locked loop to supply a reference clock to two transmitter (Tx) channels and two receiver (Rx) channels. To track the input-signal phase, the Rx channel has a clock recovery unit (CRU), which uses a phase-interpolator-based timing generator and digital loop filter. The CRU can adjust the recovered clock phase with a resolution of 1.56 ps. Two sets of two-channel transceiver units were fabricated in 0.11-/spl mu/m CMOS on a single test chip. The transceiver unit size was 1.6 mm /spl times/ 2.6 mm. The Rx sensitivity was 120-mVp-p differential with a 70-ps phase margin for a common-mode voltage ranging from 0.6 to 1.0 V. The evaluated jitter tolerance curve met the OC-192 specification. 相似文献
2.
Sachiyuki Hasegawa Kazuyuki Shimizu Takeshi Kobayashi Masakazu Matsubara 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1985,35(1):33-42
Repeated batch operation using two fermentors (RBTF) to penicillin fermentation was demonstrated by computer simulation to improve productivity. Three operation modes were compared: chemostat, repeated batch operation using a single fermentor (RBSF) and RBTF; in each case account was made of the lag period before growth. The simulated fermentor performances were assessed on the basis of the penicillin productivity and concentration; the simulation was based on published batch fermentation data. It was shown that RBTF was superior to RBSF and chemostat. The advantage of RBTF increased as the lag period became greater. 相似文献
3.
Y Koya T Matsubara T Ikeuchi S Adachi K Yamauchi 《Canadian Metallurgical Quarterly》1997,118(4):1217-1223
Vitellogenin of matrotrophic viviparous eelpout (Zoarces elongatus) was purified from estradiol-17 beta (E2) treated immature male sera by gel chromatography and anion exchange chromatography. Isolated vitellogenin has a molecular weight of 540 kDa estimated by gel chromatography. Serum levels of vitellogenin in females were measured during oocyte development and gestation by single radial immunodiffusion. Serum vitellogenin level was low (less than 0.2 mg/ml) during the early vitellogenic period, increased in the late vitellogenic period to a peak level (6.4 +/- 2.1 mg/ml) at the beginning of gestation. After that it rapidly decreased to a low level (0.1 +/- 0.1 mg/ml) during the early gestation period. Levels of vitellogenin remained low throughout the gestation period. Serum E2 levels in females showed increased from 1.3 to 3.0 ng/ml during the late vitellogenic period, and declined to 0.4 ng/ml during the early gestation period. Serum levels of E2 showed good correlation with serum vitellogenin levels, suggesting that the vitellogenin synthesis is controlled by E2 in this species. These results combined with the matrotrophic growth of embryo during gestation suggest that there is a shift in the synthesis of maternal nutritional products for embryos from the yolk to other nutrients. 相似文献
4.
H Matsubara N Oya Y Suzuki S Kajiura K Suzumori Y Matsuo T Suzuki T Hashimoto 《Canadian Metallurgical Quarterly》1997,12(5):306-308
Both choledochal cyst and congenital biliary atresia (type I cyst) may share the same ultrasonographic pattern. We report 2 cases which were shown to have cystic structures on the upper abdomen by antenatal ultrasonography. The size of the choledochal cyst found at 24 weeks' gestation increased steadily as gestational age advanced. But the size of the cyst in congenital biliary atresia found at 29 weeks' gestation remained unchanged throughout the remaining pregnancy. Cyst enlargement, therefore, may suggest the possibility of a choledochal cyst. 相似文献
5.
J Tsutsui K Kadomatsu S Matsubara A Nakagawara M Hamanoue S Takao H Shimazu Y Ohi T Muramatsu 《Canadian Metallurgical Quarterly》1993,53(6):1281-1285
Midkine (MK) and heparin-binding growth-associated molecule/pleiotrophin form a new family of heparin-binding growth/differentiation factors. We studied MK gene expression in human tumors. In normal human reference tissues, MK was highly expressed in the mucosal tissue of the small intestine, moderately in the thyroid, weakly in the tissues of the lung, colon, stomach, kidney, and spleen, and not at all in the liver. All of 6 surgically removed specimens of Wilms' tumor highly expressed MK. Also, a moderate to intense level of MK expression was noted in the majority of surgically removed hepatocellular carcinomas. The MK mRNA level was analyzed in a number of cultured and nude mice-transplanted lines of human tumors. In stomach, colon, pancreatic, lung, and esophageal carcinomas, a moderate to high level of MK expression was found in the majority of them. These results suggest an important role of MK in the development and/or biological behavior of tumors and raised a possibility to use MK as a diagnostic marker. Heparin-binding growth associated molecule/pleiotrophin mRNA was low or scarcely detectable in samples analyzed thus far except for significant levels of the expression that were observed in PA-1 teratocarcinoma cells and in some surgical specimens of Wilms' tumor. 相似文献
6.
Color‐vision deficiency is a relatively common genetic condition, which often leads to the obstruction of necessary information in colored images. It is important to minimize such inconvenient effects in communication using colored images from a universal design perspective. The universal design principle stipulates that all environments and products should be usable by all people, regardless of age, physical attributes, and ability. This article proposes a method to detect color combinations in a given image that would confuse color dichromats, and suggests a way in which to modify them to make the image easily distinguishable for both normal and dichromatic observers. Confusing color combinations were detected based on a color‐difference calculation using simulations of how the color would appear to dichromats. The confusing colors were then modified based on the minimization of an evaluation function, which was defined as the sum of the degree of confusion and the degree of color change from the original image. Several colored images obtained by the proposed method were compared with the originals by red–green dichromatic observers who judged them to be clearer, thereby confirming that the proposed method was effective for color rendering for universal design. © 2008 Wiley Periodicals, Inc. Col Res Appl, 33, 203–211, 2008 相似文献
7.
SrO and CaO, related compounds of BSCCO superconductor, are grown onto SrTiO3(100) substrates with molecular beam epitaxy(MBE) technique. During growth, the specular spots of RHEED patterns show intensity oscillations, indicating two dimensional growth. The periods of oscillations are utilized to calculate the atom fluxes. It is shown that sublimation processes of both Sr and Ca metals in the effusion cells are stable under the growth condition of oxide films. The periods of oscillations during the SrO growth are independent of substrate temperature, confirming that Sr atoms are oxidized immediately and stay on the substrate surface without re-evaporation. These informations are practically available for precise control of the atomic layer controlled MBE of BSCCO superconductor thin films.On leave from Superconductiivity Research Laboratory, ISTEC. 相似文献
8.
Nickel-based self-fluxing alloy coating extends the service life of furnace wall tubes at waste incineration plants due to
its excellent corrosion resistance and heat resistance. Fusing of such coatings by induction heating offers improved efficiency
and reliability of products. Compared with conventional plasma, flame, and high-velocity oxy-fuel spraying thermal-sprayed
coatings, induction-fused coatings provide a far stronger metallurgical bond at the interface, while minimizing the inclusion
of pores. In addition, the tubes are less costly than those with welded coatings, and the process reduces the distortion of
the products, facilitating easier final assembly. A successful experimental application of 11 units in a waste incinerator
revealed virtually no corrosion on the exposed surfaces, and showed an improved water heating efficiency over that of the
original tubes. Such units are now being employed in four incinerators in Taiwan, and continuing tests are showing great promise. 相似文献
9.
Satoshi lio Masakazu Watanabe Masaru Matsubara Yasushi Matsuo 《Journal of the American Ceramic Society》1989,72(10):1880-1884
The improvement of mechanical properties of Al2 O3 /SiC whisker composites has been studied with emphasis on the effects of the whisker content and of the hot-pressing temperature. Mechanical properties such as fracture toughness and fracture strength increased with increasing whisker content up to 40 wt%. In the case of the high SiC whisker content of 40 wt%, fracture toughness of the sample hot-pressed at 1900° decreased significantly, in spite of densification, compared with one hot-pressed at 1850°. Fracture toughness strongly depended on the microstructure, especially the distribution of SiC whiskers rather than the grain size of the Al2 O3 matrix. 相似文献
10.
Time-series primitive static states for detailing work state and flow of human-operated work machine
This paper proposes a quantification method for a comprehensive work flow in construction work for describing work states in more detail on the basis of analyzing state transitions of primitive static states (PSS), which consist of 16 symbolic work states defined by using on-off state of the lever operations and joint loads for the manipulator and end-effector. On the basis of the state transition rules derived from a transition-condition analysis, practical state transitions (PST), which are common and frequent transitions in arbitrary construction work, are defined. PST can be classified into essential state transition (EST) or nonessential state transitions (NST). EST extracts common phases of work progress and estimates positional relations between a manipulator and an object. NST reveals wasted movements that degrade the efficiency and quality of work. To evaluate comprehensive work flows modeled by combining EST and NST, work-analysis experiments using our instrumented setup were conducted. Results indicate that all the PSS definitely changes on the basis of PST under various work conditions, and work analysis using EST and NST easily reveals work characteristics and untrained tasks related to wasted movements. 相似文献