全文获取类型
收费全文 | 73篇 |
免费 | 1篇 |
专业分类
化学工业 | 7篇 |
机械仪表 | 1篇 |
建筑科学 | 6篇 |
能源动力 | 2篇 |
轻工业 | 11篇 |
无线电 | 7篇 |
一般工业技术 | 7篇 |
冶金工业 | 29篇 |
原子能技术 | 1篇 |
自动化技术 | 3篇 |
出版年
2023年 | 1篇 |
2022年 | 1篇 |
2020年 | 2篇 |
2017年 | 1篇 |
2016年 | 1篇 |
2013年 | 1篇 |
2012年 | 1篇 |
2011年 | 4篇 |
2010年 | 1篇 |
2009年 | 1篇 |
2008年 | 4篇 |
2007年 | 5篇 |
2006年 | 4篇 |
2005年 | 5篇 |
2004年 | 3篇 |
2003年 | 1篇 |
2002年 | 2篇 |
2001年 | 1篇 |
1999年 | 1篇 |
1998年 | 6篇 |
1997年 | 4篇 |
1996年 | 1篇 |
1995年 | 3篇 |
1994年 | 2篇 |
1987年 | 2篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1978年 | 3篇 |
1977年 | 1篇 |
1976年 | 3篇 |
1970年 | 1篇 |
1966年 | 1篇 |
1964年 | 1篇 |
1960年 | 1篇 |
排序方式: 共有74条查询结果,搜索用时 0 毫秒
71.
Segmentation, registration, and measurement of shape variation via image object shape 总被引:1,自引:0,他引:1
Pizer SM Fritsch DS Yushkevich PA Johnson VE Chaney EL 《IEEE transactions on medical imaging》1999,18(10):851-865
A model of object shape by nets of medial and boundary primitives is justified as richly capturing multiple aspects of shape and yet requiring representation space and image analysis work proportional to the number of primitives. Metrics are described that compute an object representation's prior probability of local geometry by reflecting variabilities in the net's node and link parameter values, and that compute a likelihood function measuring the degree of match of an image to that object representation. A paradigm for image analysis of deforming such a model to optimize a posteriori probability is described, and this paradigm is shown to be usable as a uniform approach for object definition, object-based registration between images of the same or different imaging modalities, and measurement of shape variation of an abnormal anatomical object, compared with a normal anatomical object. Examples of applications of these methods in radiotherapy, surgery, and psychiatry are given. 相似文献
72.
Speciation and release kinetics of cadmium in an alkaline paddy soil under various flooding periods and draining conditions 总被引:6,自引:0,他引:6
Khaokaew S Chaney RL Landrot G Ginder-Vogel M Sparks DL 《Environmental science & technology》2011,45(10):4249-4255
This study determined Cd speciation and release kinetics in a Cd-Zn cocontaminated alkaline paddy soil, under various flooding periods and draining conditions, by employing synchrotron-based techniques, and a stirred-flow kinetic method. Results revealed that varying flooding periods and draining conditions affected Cd speciation and its release kinetics. Linear least-squares fitting (LLSF) of bulk X-ray absorption fine structure (XAFS) spectra of the air-dried, and the 1 day-flooded soil samples, showed that at least 50% of Cd was bound to humic acid. Cadmium carbonates were found as the major species at most flooding periods, while a small amount of cadmium sulfide was found after the soils were flooded for longer periods. Under all flooding and draining conditions, at least 14 mg/kg Cd was desorbed from the soil after a 2-hour desorption experiment. The results obtained by micro X-ray fluorescence (μ-XRF) spectroscopy showed that Cd was less associated with Zn than Ca, in most soil samples. Therefore, it is more likely that Cd and Ca will be present in the same mineral phases rather than Cd and Zn, although the source of these two latter elements may originate from the same surrounding Zn mines in the Mae Sot district. 相似文献
73.
Oxidation of glyceraldehyde−3−phosphate dehydrogenase (GAPDH) by reactive oxygen species such as H2O2 activate pleiotropic signaling pathways is associated with pathophysiological cell fate decisions. Oxidized GAPDH binds chaperone proteins with translocation of the complex to the nucleus and mitochondria initiating autophagy and cellular apoptosis. In this study, we establish the mechanism by which H2O2−oxidized GAPDH subunits undergo a subunit conformational rearrangement. H2O2 oxidizes both the catalytic cysteine and a vicinal cysteine (four residues downstream) to their respective sulfenic acids. A ‘two−cysteine switch’ is activated, whereby the sulfenic acids irreversibly condense to an intrachain thiosulfinic ester resulting in a major metastable subunit conformational rearrangement. All four subunits of the homotetramer are uniformly and independently oxidized by H2O2, and the oxidized homotetramer is stabilized at low temperatures. Over time, subunits unfold forming disulfide−linked aggregates with the catalytic cysteine oxidized to a sulfinic acid, resulting from thiosulfinic ester hydrolysis via the highly reactive thiosulfonic ester intermediate. Molecular Dynamic Simulations provide additional mechanistic insights linking GAPDH subunit oxidation with generating a putative signaling conformer. The low−temperature stability of the H2O2−oxidized subunit conformer provides an operable framework to study mechanisms associated with gain−of−function activities of oxidized GAPDH to identify novel targets for the treatment of neurodegenerative diseases. 相似文献
74.
This study focuses on the early stage of polymer-derived SiOC ceramic conversion. We demonstrate that the perceived SiOC phase separation is nonexistent. Instead, SiO2 and free carbon clusters form first and then carbothermal reduction sets in to induce SiOC formation. Such fundamental understanding is supported by both synchrotron X-ray diffraction study and reactive force field simulation. This work for the first time unifies the understanding of atomic evolution process of polysiloxane-based polymer to ceramic conversion. 相似文献