全文获取类型
收费全文 | 360篇 |
免费 | 2篇 |
国内免费 | 2篇 |
专业分类
化学 | 129篇 |
晶体学 | 1篇 |
力学 | 10篇 |
数学 | 28篇 |
物理学 | 196篇 |
出版年
2018年 | 4篇 |
2016年 | 3篇 |
2015年 | 3篇 |
2013年 | 9篇 |
2012年 | 6篇 |
2011年 | 11篇 |
2010年 | 4篇 |
2009年 | 7篇 |
2008年 | 10篇 |
2007年 | 6篇 |
2006年 | 15篇 |
2005年 | 16篇 |
2004年 | 7篇 |
2002年 | 12篇 |
2001年 | 10篇 |
2000年 | 7篇 |
1999年 | 3篇 |
1998年 | 3篇 |
1997年 | 3篇 |
1996年 | 11篇 |
1995年 | 13篇 |
1994年 | 8篇 |
1993年 | 15篇 |
1992年 | 12篇 |
1991年 | 7篇 |
1990年 | 8篇 |
1989年 | 20篇 |
1988年 | 4篇 |
1987年 | 8篇 |
1986年 | 8篇 |
1985年 | 8篇 |
1984年 | 4篇 |
1982年 | 5篇 |
1981年 | 5篇 |
1980年 | 2篇 |
1979年 | 6篇 |
1978年 | 3篇 |
1977年 | 7篇 |
1976年 | 7篇 |
1975年 | 2篇 |
1974年 | 4篇 |
1973年 | 2篇 |
1968年 | 2篇 |
1967年 | 4篇 |
1966年 | 2篇 |
1959年 | 4篇 |
1928年 | 2篇 |
1918年 | 3篇 |
1889年 | 2篇 |
1883年 | 2篇 |
排序方式: 共有364条查询结果,搜索用时 609 毫秒
1.
The morphologies of solvent-free, microporous, mechanically self-supporting cylinders of linear polyethylene and isotactic polypropylene, crystallized from solution in supercritical propane, were examined by an SEM technique. The morphology of gels (or foams), obtained with little or no shrinkage from 2% to 35% solutions by weight of polyethylene (99% to 85% porosities), is shown in some detail. Lamellae with very little or considerable mutual organization occur, often in the form of stacks with straight or coiled axes (axialites). Further growth of these can lead to particles with a roughly spherical overall shape and a predominantly radial orientation of the lamellae at the particle surface. Subcooled isotactic polypropylene, on the other hand, crystallizes in the form of perfectly shaped birefringent microspheres of very uniform size. ©1995 John Wiley & Sons, Inc. 相似文献
2.
3.
Bortoletto D Goldberg M Horwitz N Mestayer MD Moneti GC Sharma V Shipsey IP Skwarnicki T Csorna SE Letson T Brock IC Ferguson T Artuso M Bebek C Berkelman K Blucher E Byrd J Cassel DG Cheu E Coffman DM Crawford G DeSalvo R DeWire JW Drell PS Ehrlich R Galik RS Gittelman B Gray SW Halling AM Hartill DL Heltsley BK Kandaswamy J Kowalewski R Kreinick DL Kubota Y Lewis JD Mistry NB Mueller J Namjoshi R Nandi S Nordberg E O'Grady C Peterson D Pisharody M Riley D Sapper M Silverman A Stone S Worden H 《Physical review letters》1989,62(21):2436-2439
4.
5.
Alam MS Katayama N Kim IJ Li WC Lou XC Sun CR Bortoletto D Goldberg M Horwitz N Mestayer MD Moneti GC Sharma V Shipsey IP Skwarnicki T Csorna SE Letson T Brock IC Ferguson T Artuso M Bebek C Berkelman K Blucher E Byrd J Cassel DG Cheu E Coffman DM Crawford G DeSalvo R DeWire JW Drell PS Ehrlich R Galik RS Gittelman B Gray SW Halling AM Hartill DL Heltsley BK Kandaswamy J Kowalewski R Kreinick DL Kubota Y Lewis JD Mistry NB Mueller J Namjoshi R Nandi S Nordberg E O'Grady C Peterson D Pisharody M 《Physical review D: Particles and fields》1989,40(11):3790
6.
Chen Wang Amit Fischer Avner Ehrlich Yaakov Nahmias Itamar Willner 《Chemical science》2020,11(17):4516
The enzymes glucose oxidase (GOx), acetylcholine esterase (AchE) and urease that drive biocatalytic transformations to alter pH, are integrated into pH-responsive DNA-based hydrogels. A two-enzyme-loaded hydrogel composed of GOx/urease or AchE/urease and a three-enzyme-loaded hydrogel composed of GOx/AchE/urease are presented. The biocatalytic transformations within the hydrogels lead to the dictated reconfiguration of nucleic acid bridges and the switchable control over the stiffness of the respective hydrogels. The switchable stiffness features are used to develop biocatalytically guided shape-memory and self-healing matrices. In addition, loading of GOx/insulin in a pH-responsive DNA-based hydrogel yields a glucose-triggered matrix for the controlled release of insulin, acting as an artificial pancreas. The release of insulin is controlled by the concentrations of glucose, hence, the biocatalytic insulin-loaded hydrogel provides an interesting sense-and-treat carrier for controlling diabetes.Biocatalytic control over the stiffness of pH-responsive hydrogels is applied to develop shape-memory, self-healing and controlled release matrices. 相似文献
7.
Günter Ehrlich Thomas Nestler Rainer Voigtmann Willi Moldenhauer 《Mikrochimica acta》1989,98(4-6):249-258
To compare concentration profiles in solids in an objective manner, a multi-dimensional generalization of the comparison of two means by Student'st-test is proposed. The approach is based on piecewise modelling the profiles using rougha priori information, estimating the model parameters and their covariance matrix and comparing the estimated parameters by use of multidimensional test variables. The piecewise modelling is treated in the most important cases in such a way that the partial functions are straight lines or cubic polynoms (splines) with continuity at all knots in each case. It enables us to compare whole profiles as well as the most relevant parts of them. Two ways of estimating the covariance matrix as a generalization of the variance estimation are discussed. The approach is useful for any kind of line profiles if rough information on the profile type is available. As an example SIMS depth-profiles of aluminum obtained from thin-layer systems after different technological heat treatments are considered. These profiles are modeled by three straight lines. 相似文献
8.
9.
Balest R Cho K Ford WT Lohner M Park H Rankin P Smith JG Alexander JP Bebek C Berger BE Berkelman K Bloom K Browder TE Cassel DG Cho HA Coffman DM Crowcroft DS Dickson M Drell PS Dumas DJ Ehrlich R Elia R Gaidarev P Garcia-Sciveres M Gittelman B Gray SW Hartill DL Heltsley BK Henderson S Jones CD Jones SL Kandaswamy J Katayama N Kim PC Kreinick DL Lee T Liu Y Ludwig GS Masui J Mevissen J Mistry NB Ng CR Nordberg E Patterson JR Peterson D Riley D Soffer A Avery P Freyberger A Lingel K Prescott C 《Physical review letters》1995,75(21):3809-3813
10.
Barish B Chadha M Chan S Cowen DF Eigen G Miller JS O'Grady C Urheim J Weinstein AJ Acosta D Athanas M Masek G Paar HP Gronberg J Kutschke R Menary S Morrison RJ Nakanishi S Nelson HN Nelson TK Qiao C Richman JD Ryd A Tajima H Sperka D Witherell MS Procario M Balest R Cho K Daoudi M Ford WT Johnson DR Lingel K Lohner M Rankin P Smith JG Alexander JP Bebek C Berkelman K Bloom K Browder TE Cassel DG Cho HA Coffman DM Crowcroft DS Drell PS Ehrlich R Gaidarev P Galik RS Garcia-Sciveres M Geiser B 《Physical review D: Particles and fields》1995,51(3):1014-1033