全文获取类型
收费全文 | 918篇 |
免费 | 0篇 |
国内免费 | 1篇 |
专业分类
化学工业 | 20篇 |
金属工艺 | 2篇 |
轻工业 | 2篇 |
水利工程 | 1篇 |
石油天然气 | 2篇 |
无线电 | 12篇 |
一般工业技术 | 9篇 |
冶金工业 | 852篇 |
原子能技术 | 1篇 |
自动化技术 | 18篇 |
出版年
2017年 | 3篇 |
2016年 | 2篇 |
2014年 | 1篇 |
2013年 | 3篇 |
2011年 | 2篇 |
2010年 | 2篇 |
2008年 | 3篇 |
2007年 | 5篇 |
2006年 | 2篇 |
2005年 | 3篇 |
2004年 | 2篇 |
2003年 | 9篇 |
2002年 | 1篇 |
2001年 | 4篇 |
2000年 | 1篇 |
1999年 | 25篇 |
1998年 | 240篇 |
1997年 | 148篇 |
1996年 | 106篇 |
1995年 | 55篇 |
1994年 | 38篇 |
1993年 | 44篇 |
1992年 | 4篇 |
1991年 | 10篇 |
1990年 | 3篇 |
1989年 | 9篇 |
1988年 | 12篇 |
1987年 | 6篇 |
1986年 | 13篇 |
1985年 | 14篇 |
1983年 | 2篇 |
1982年 | 10篇 |
1981年 | 7篇 |
1980年 | 8篇 |
1979年 | 1篇 |
1978年 | 5篇 |
1977年 | 25篇 |
1976年 | 90篇 |
1955年 | 1篇 |
排序方式: 共有919条查询结果,搜索用时 0 毫秒
121.
We present three experiments designed to investigate the role of prosody during sentence processing. The first investigated the question of whether an utterance's prosodic contour influences its comprehension on-line. We spliced the beginning and end portions of direct object and embedded clause sentences and observed the consequent effects on comprehension using a dual-task procedure to measure processing load. Our second experiment sought to determine whether the constituent structure of these sentences could be reliably predicted using prosodic information. We found that the duration and F0 contour associated with the main-clause verb and the following NP reliably distinguished between the direct object and embedded clause constructions. In the final experiment, we manipulated the duration of the main-clause verb and found that subjects used this information to guide their initial parse during on-line sentence comprehension. The need for a model of sentence processing that addresses the use of prosodic information is discussed. 相似文献
122.
123.
CM Martinez ML Gaspar EA Ribes AM Amenos EF Prevosti LP Robert 《Canadian Metallurgical Quarterly》1976,116(1):94-95
A case of pneumomediastinum, which appeared after a biopsy of the right kidney by minimal lumbotomy, is reported. The anatomicopathological condition of the renal fragment obtained was judged to be focal and segmental hyalinosis. We wish to emphasize the rarity of such a complication, the type of electrocardiographic changes observed, and the rapid and spontaneous recuperation of the patient without further repercussions. 相似文献
124.
T Rantanen JM Guralnik S Leveille G Izmirlian R Hirsch E Simonsick S Ling LP Fried 《Canadian Metallurgical Quarterly》1998,53(5):B355-B361
This study examines racial differences in muscle strength, and associations of muscle strength to level of physical activity and severity of disability, among a community sample of 254 black and 665 white, moderately to severely disabled women aged 65 and older. Potential confounders that were adjusted for in the models included age, body weight and height, joint pain, number of chronic conditions, and socioeconomic status. Hand grip, hip flexion, and knee extension forces were measured using portable hand-held dynamometers in the participants' homes. Hand grip strength was measured as the maximal isometric force. Hip flexion and knee extension forces were measured as the greatest force the tester had to apply to break the isometric contraction. A declining strength gradient was observed with increasing severity of disability and for decreasing level of physical activity in both races. At equal levels of disability or physical activity, blacks had better hand grip and hip flexion strength, but knee extension strength did not differ by race. The greater hand grip and hip flexion strength found in black women may be related to their greater muscle mass and known racial differences in body dimensions. No consistent racial differences were observed in the relationship between physical activity and muscle strength, or muscle strength and disability, suggesting that the role of muscle strength in the disablement process does not differ between races. Physical activity and exercise programs may be feasible ways to prevent worsening of disability in blacks and whites. 相似文献
125.
GS Orsmond L Knight LP Dehner DM Nicoloff M Nesbitt FB Bessinger 《Canadian Metallurgical Quarterly》1976,54(5):837-843
A 12-year-old girl, who had had an above-knee amputation of the left leg for a soft tissue sarcoma six years prior to this admission, presented with syncope, angina, and signs of aortic stenosis. Echocardiography demonstrated a mass arising from the interventricular septum with obstruction of the left ventricular outflow tract and aortic valve. Cardiac catheterization and angiography confirmed these findings. At operation, a tumor was found involving the interventricular septum. Histologically, it was an alveolar rhabdomyosarcoma, and it appeared similar to the previous tumor. The patient was treated by partial surgical resection, cytotoxic drugs and localized radiation therapy and has been followed by serial echocardiography. 相似文献
126.
LP Jager 《Canadian Metallurgical Quarterly》1976,221(1):40-53
Passive film and accelerated corrosion tests were performed on both wrought AISI 316L stainless steel and wrought Vitallium (Haynes Stellite 25) Charnley Type cement restrictors. The morphology and incidence of corrosion at the wire-wire crevices and the methacrylate-metal crevices were determined by scanning electron microscopy. The results are interpreted in view of the previously-documented crevice corrosion susceptibility of these two alloys. 相似文献
127.
128.
129.
130.
A voltage controlled negative differential resistance (NDR) in n-channel MOSFETs of (100) orientation is investigated for lattice temperatures between 1.5 and 100 K in transverse magnetic fields up to 7 Tesla. By variation of the length of the pulses and by investigating samples of different geometry it is shown, that the NDR is not caused by lattice heating. Position and magnitude of the NDR depend substantially on the magnetic field. The observed effects can be explained by cooling of the hot carriers by the magnetic field. 相似文献