全文获取类型
收费全文 | 84篇 |
免费 | 10篇 |
专业分类
电工技术 | 1篇 |
综合类 | 1篇 |
化学工业 | 38篇 |
机械仪表 | 2篇 |
建筑科学 | 2篇 |
能源动力 | 4篇 |
轻工业 | 6篇 |
无线电 | 4篇 |
一般工业技术 | 17篇 |
冶金工业 | 1篇 |
自动化技术 | 18篇 |
出版年
2021年 | 7篇 |
2020年 | 6篇 |
2019年 | 1篇 |
2018年 | 3篇 |
2017年 | 6篇 |
2015年 | 4篇 |
2014年 | 5篇 |
2013年 | 5篇 |
2012年 | 7篇 |
2011年 | 6篇 |
2010年 | 6篇 |
2009年 | 5篇 |
2008年 | 7篇 |
2007年 | 6篇 |
2006年 | 2篇 |
2005年 | 1篇 |
2004年 | 4篇 |
2003年 | 3篇 |
2002年 | 1篇 |
2000年 | 1篇 |
1999年 | 2篇 |
1996年 | 1篇 |
1986年 | 1篇 |
1981年 | 1篇 |
1979年 | 1篇 |
1976年 | 1篇 |
1975年 | 1篇 |
排序方式: 共有94条查询结果,搜索用时 31 毫秒
21.
Modi K Fazio R Pascazio S Vedral V Yuasa K 《Philosophical transactions. Series A, Mathematical, physical, and engineering sciences》2012,370(1976):4810-4820
We construct a quantumness witness following the work of Alicki & van Ryn (AvR). We reformulate the AvR test by defining it for quantum states rather than for observables. This allows us to identify the necessary quantities and resources to detect quantumness for any given system. The first quantity turns out to be the purity of the system. When applying the witness to a system with even moderate mixedness, the protocol is unable to reveal any quantumness. We then show that having many copies of the system leads the witness to reveal quantumness. This seems contrary to the Bohr correspondence, which asserts that, in the large-number limit, quantum systems become classical, whereas the witness shows quantumness when several non-quantum systems, as determined by the witness, are considered together. However, the resources required to detect the quantumness increase dramatically with the number of systems. We apply the quantumness witness for systems that are highly mixed but in the large-number limit that resembles nuclear magnetic resonance (NMR) systems. We make several conclusions about detecting quantumness in NMR-like systems. 相似文献
22.
Chiral Resolution and Pharmacological Characterization of the Enantiomers of the Hsp90 Inhibitor 2‐Amino‐7‐[4‐fluoro‐2‐(3‐pyridyl)phenyl]‐4‐methyl‐7,8‐dihydro‐6H‐quinazolin‐5‐one Oxime 下载免费PDF全文
Dr. Raffaella Amici Dr. Chiara Bigogno Dr. Roberto Boggio Dr. Andrea Colombo Dr. Stephen M. Courtney Dr. Roberto Dal Zuffo Dr. Giulio Dondio Dr. Fulvia Fusar Dr. Stefania Gagliardi Prof. Dr. Saverio Minucci Dr. Marco Molteni Dr. Christian A. G. N. Montalbetti Dr. Annalisa Mortoni Dr. Mario Varasi Dr. Stefania Vultaggio Dr. Ciro Mercurio 《ChemMedChem》2014,9(7):1574-1585
Heat‐shock protein 90 (Hsp90) is a molecular chaperone involved in the stabilization of key oncogenic signaling proteins, and therefore, inhibition of Hsp90 represents a new strategy in cancer therapy. 2‐Amino‐7‐[4‐fluoro‐2‐(3‐pyridyl)phenyl]‐4‐methyl‐7,8‐dihydro‐6H‐quinazolin‐5‐one oxime is a racemic Hsp90 inhibitor that targets the N‐terminal adenosine triphosphatase site. We developed a method to resolve the enantiomers and evaluated their inhibitory activity on Hsp90 and the consequent antitumor effects. The (S) stereoisomer emerged as a potent Hsp90 inhibitor in biochemical and cellular assays. In addition, this enantiomer exhibited high oral bioavailability in mice and excellent antitumor activity in two different human cancer xenograft models. 相似文献
23.
MT Fadda F Saverio De Ponte DJ Bottini G Iannetti 《Canadian Metallurgical Quarterly》1996,7(3):207-223
Orbital surgery is of critical importance within the framework of craniofacial surgery. The conical conformation of orbits requires analysis and surgical procedure planning methods involving all three dimensions. We present our protocol for the analysis and our three-dimensional surgical procedure plan to treat orbital malformations using teleradiography and two- and three-dimensional computed tomographic imaging. A number of clinical cases treated according to this approach are also presented. 相似文献
24.
The rates of initiation for the copolymerization of styrene and methyl methacrylate at 50°, in different reaction media (bulk, acetone, dimethylformamide and dioxane) have been determined by using the isotopic labelling technique (14C - azobisisobutyronitrile). For all mixtures, except dioxane, the experimental data do not support the linear interpolation of the initiation rates, which is usually adopted in literature. In the whole range of monomer feed compositions, any modification of the reaction medium causes a relevant change of the initiation rate, so that the overall pattern is markedly modified. The strongest solvent effect is given by dioxane, which reduces the initiation rates for all monomer mixtures.The radioactive tracer method also enables the determination of the modes of termination, which occur almost exclusively by combination for monomer feed compositions up to about 70 molar % of methyl methacrylate. The ratios obtained by g.p.c. confirm the general trend of the termination mechanisms as a function of monomer mixture and reaction medium. 相似文献
25.
Carmen Chiappori Saverio Russo Antonio Turturro Alberto Passerone Roberto Sangiorgi 《Polymer》1981,22(4):534-538
A study of the adhesion of molten nylon-6 to glass, vitreous silica and dehydrated silica is performed by the sessile drop method at 243°C. The influence of polymerization conditions, nature of substrate, thermal pretreatment of the polymer and lithium chloride addition on wettability is examined. The most relevant results show that thermal pretreatment of the polymer is a determining step in wettability and that LiCl addition causes an increase of contact angle, as a consequence of the decrease in the substrate-molten polymer interactions. The results are interpreted by means of an interfacial model based on additive polar and dispersion forces. 相似文献
26.
Highly Efficient Rubrene–Graphene Charge‐Transfer Interfaces as Phototransistors in the Visible Regime 下载免费PDF全文
Gareth F. Jones Rui M. Pinto Adolfo De Sanctis V. Karthik Nagareddy C. David Wright Helena Alves Monica F. Craciun Saverio Russo 《Advanced materials (Deerfield Beach, Fla.)》2017,29(41)
Atomically thin materials such as graphene are uniquely responsive to charge transfer from adjacent materials, making them ideal charge‐transport layers in phototransistor devices. Effective implementation of organic semiconductors as a photoactive layer would open up a multitude of applications in biomimetic circuitry and ultra‐broadband imaging but polycrystalline and amorphous thin films have shown inferior performance compared to inorganic semiconductors. Here, the long‐range order in rubrene single crystals is utilized to engineer organic‐semiconductor–graphene phototransistors surpassing previously reported photogating efficiencies by one order of magnitude. Phototransistors based upon these interfaces are spectrally selective to visible wavelengths and, through photoconductive gain mechanisms, achieve responsivity as large as 107 A W?1 and a detectivity of 9 × 1011 Jones at room temperature. These findings point toward implementing low‐cost, flexible materials for amplified imaging at ultralow light levels. 相似文献
27.
Lifetime total and beverage specific - alcohol intake and prostate cancer risk: a case-control study
Maddalena Barba Susan E McCann Holger J Schünemann Saverio Stranges Barbara Fuhrman Sabino De Placido Giuseppe Carruba Jo L Freudenheim Maurizio Trevisan Marcia Russell Tom Nochajski Paola Muti 《Nutrition journal》2004,3(1):1-8
Background
We investigated lifetime alcohol consumption and prostate cancer risk in a case-control study conducted in Buffalo, NY (1998–2001).Methods
The study included 88 men, aged 45 to 85 years with incident, histologically-confirmed prostate cancer and 272 controls. We conducted extensive in-person interviews regarding lifetime alcohol consumption and other epidemiologic data.Results
Prostate cancer risk was not associated with lifetime intake of total and beverage specific ethanol. In addition we found no association with number of drinks per day (average drinks per day over the lifetime) or drinks per drinking day (average drinks per day on drinking days only over the lifetime). However, we observed an inverse association with the total number of drinking years. Men in the lowest tertile of total drinking years had a two-fold prostate cancer risk than men in the highest tertile (OR 2.16, 95% CI 0.98–4.78, p for trend <0.05).Conclusion
Our results suggest that alcohol intake distribution across lifetime may play a more important role in prostate cancer etiology than total lifetime consumption. 相似文献28.
29.
30.
TCP Westwood: End-to-End Congestion Control for Wired/Wireless Networks 总被引:11,自引:0,他引:11
Casetti Claudio Gerla Mario Mascolo Saverio Sanadidi M.Y. Wang Ren 《Wireless Networks》2002,8(5):467-479
TCP Westwood (TCPW) is a sender-side modification of the TCP congestion window algorithm that improves upon the performance of TCP Reno in wired as well as wireless networks. The improvement is most significant in wireless networks with lossy links. In fact, TCPW performance is not very sensitive to random errors, while TCP Reno is equally sensitive to random loss and congestion loss and cannot discriminate between them. Hence, the tendency of TCP Reno to overreact to errors. An important distinguishing feature of TCP Westwood with respect to previous wireless TCP extensions is that it does not require inspection and/or interception of TCP packets at intermediate (proxy) nodes. Rather, TCPW fully complies with the end-to-end TCP design principle. The key innovative idea is to continuously measure at the TCP sender side the bandwidth used by the connection via monitoring the rate of returning ACKs. The estimate is then used to compute congestion window and slow start threshold after a congestion episode, that is, after three duplicate acknowledgments or after a timeout. The rationale of this strategy is simple: in contrast with TCP Reno which blindly halves the congestion window after three duplicate ACKs, TCP Westwood attempts to select a slow start threshold and a congestion window which are consistent with the effective bandwidth used at the time congestion is experienced. We call this mechanism faster recovery. The proposed mechanism is particularly effective over wireless links where sporadic losses due to radio channel problems are often misinterpreted as a symptom of congestion by current TCP schemes and thus lead to an unnecessary window reduction. Experimental studies reveal improvements in throughput performance, as well as in fairness. In addition, friendliness with TCP Reno was observed in a set of experiments showing that TCP Reno connections are not starved by TCPW connections. Most importantly, TCPW is extremely effective in mixed wired and wireless networks where throughput improvements of up to 550% are observed. Finally, TCPW performs almost as well as localized link layer approaches such as the popular Snoop scheme, without incurring the overhead of a specialized link layer protocol. 相似文献