全文获取类型
收费全文 | 71篇 |
免费 | 6篇 |
专业分类
化学 | 21篇 |
综合类 | 1篇 |
数学 | 33篇 |
物理学 | 22篇 |
出版年
2023年 | 1篇 |
2022年 | 2篇 |
2020年 | 2篇 |
2017年 | 6篇 |
2016年 | 1篇 |
2015年 | 8篇 |
2014年 | 3篇 |
2013年 | 10篇 |
2012年 | 3篇 |
2011年 | 2篇 |
2010年 | 2篇 |
2009年 | 4篇 |
2008年 | 7篇 |
2007年 | 4篇 |
2006年 | 2篇 |
2005年 | 4篇 |
2004年 | 1篇 |
2003年 | 2篇 |
2002年 | 2篇 |
2001年 | 1篇 |
2000年 | 1篇 |
1999年 | 1篇 |
1998年 | 1篇 |
1997年 | 2篇 |
1995年 | 1篇 |
1993年 | 1篇 |
1986年 | 1篇 |
1983年 | 1篇 |
1977年 | 1篇 |
排序方式: 共有77条查询结果,搜索用时 15 毫秒
11.
We consider a problem of allocating indivisible objects when agents may desire to consume more than one object and no monetary
transfers are allowed. We are interested in allocation rules that satisfy desirable properties from an economic and social
point of view. In addition to strategy-proofness and Pareto efficiency, we consider consistency and two solidarity properties
(replacement-domination and population-monotonicity). In most of the cases, these properties are satisfied only by serially
dictatorial rules.
Received: November 1999/Final version: December 2001 相似文献
12.
具有独立子块的大系统目标规划问题的解法 总被引:5,自引:0,他引:5
分解之后如何进行协调解决大系统规划问题的关键.本文通过利用子系统目标值所提供的信息进行大系统分解之后的协调,并提出了求解具有独立子块的大系统规划问题的串式调优法,同时研究了有关原问题和各子问题最优解的性质. 相似文献
13.
均匀设计抽样的应用 总被引:3,自引:0,他引:3
王兆军 《高校应用数学学报(A辑)》1997,(3):299-310
均匀设计抽样是张润楚和王兆军提出的,并且张润楚和王兆军从理论上证明了它的优良性质。本文考虑了均匀设计抽样在求函数的最大值,积分的近似计算,回归直线的拟合和极大似然估计的求取方面的应用。模拟的结果再次说明了均匀设计抽样的优良性。 相似文献
14.
Serially coupled capillary columns supercritical fluid chromatography with midpoint pressure control
Two capillary columns of different polarities were coupled in series by means of a coupling restrictor. The pressure of the first column and the midpoint pressure (between the coupling restrictor and the second column) were controlled independently of each other using two pumps. The selectivity of this separation system was highly dependent on the pressure difference and could be continuously changed between those of two columns. The pressure difference could be changed even in course of separation for fine tuning of the selectivity. Several examples were shown to demonstrate the utility of this method. 相似文献
15.
LabVIEW下CASSY软件的实现 总被引:1,自引:0,他引:1
主要介绍了如何在LabVIEW平面下直接与CASSY实验系统的连接。给出了用LabVIEW软件实现细节。同时介绍了利用CASSY实验系统基于串口的高频信号采集的方法。 相似文献
16.
F.?Y.?Kuo W.?T.?M.?DunsmuirEmail author I.?H.?Sloan M.?P.?Wand R.?S.?Womersley 《Methodology and Computing in Applied Probability》2008,10(2):239-275
Highly structured generalised response models, such as generalised linear mixed models and generalised linear models for time
series regression, have become an indispensable vehicle for data analysis and inference in many areas of application. However,
their use in practice is hindered by high-dimensional intractable integrals. Quasi-Monte Carlo (QMC) is a dynamic research
area in the general problem of high-dimensional numerical integration, although its potential for statistical applications
is yet to be fully explored. We survey recent research in QMC, particularly lattice rules, and report on its application to
highly structured generalised response models. New challenges for QMC are identified and new methodologies are developed.
QMC methods are seen to provide significant improvements compared with ordinary Monte Carlo methods.
相似文献
17.
针对大型直线感应加速器单次工作的特点,研制了一种电容放电式脉冲励磁电源。该电源利用电容器的储能特性,取代常规电源的变压整流滤波部分,先对其以小电流恒流充电,然后再以大电流恒流放电来获得直线感应加速器励磁电流。对这种电源进行了理论分析和模拟计算,模拟结果与实验结果基本一致。实验结果表明:这种电源能够脉冲工作,同时输入功率大幅度降低,在输出电流500 A,持续时间0.3 s时,输入功率400 W,输出功率25 kW,电流稳定度0.2%, 谐波小, 电流纹波小,所用电容器100块左右(33 mF),经济上也可承受,是一种非常适合直线感应加速器的励磁电源。 相似文献
18.
19.
Michal Zapadlo Ján Krupčík Pavel Májek Daniel W. Armstrong Pat Sandra 《Journal of chromatography. A》2010,1217(37):5859-5867
The orthogonality of three columns coupled in two series was studied for the congener specific comprehensive two-dimensional GC separation of polychlorinated biphenyls (PCBs). A non-polar capillary column coated with poly(5%-phenyl–95%-methyl)siloxane was used as the first (1D) column in both series. A polar capillary column coated with 70% cyanopropyl-polysilphenylene-siloxane or a capillary column coated with the ionic liquid 1,12-di(tripropylphosphonium)dodecane bis(trifluoromethane-sulfonyl)imide were used as the second (2D) columns. Nine multi-congener standard PCB solutions containing subsets of all native 209 PCBs, a mixture of 209 PCBs as well as Aroclor 1242 and 1260 formulations were used to study the orthogonality of both column series. Retention times of the corresponding PCB congeners on 1D and 2D columns were used to construct retention time dependences (apex plots) for assessing orthogonality of both columns coupled in series. For a visual assessment of the peak density of PCBs congeners on a retention plane, 2D images were compared. The degree of orthogonality of both column series was, along the visual assessment of distribution of PCBs on the retention plane, evaluated also by Pearson's correlation coefficient, which was found by correlation of retention times tR,i,2D and tR,i,1D of corresponding PCB congeners on both column series. It was demonstrated that the apolar + ionic liquid column series is almost orthogonal both for the 2D separation of PCBs present in Aroclor 1242 and 1260 formulations as well as for the separation of all of 209 PCBs. All toxic, dioxin-like PCBs, with the exception of PCB 118 that overlaps with PCB 106, were resolved by the apolar/ionic liquid series while on the apolar/polar column series three toxic PCBs overlapped (105 + 127, 81 + 148 and 118 + 106). 相似文献
20.
Determination of taurine in human tear fluid by capillary electrophoresis with indirect amperometric detection based on electrogenerated bromine 下载免费PDF全文
Fuying Du Wenfeng Zhao Shunan Cao Ying‐Sing Fung 《Journal of separation science》2015,38(18):3271-3278
A new method for the determination of taurine was developed based on indirect amperometric detection after capillary electrophoresis. A serial dual‐electrode detector comprising an on column Pt film electrode (upstream electrode) and an end column Pt microdisk electrode (downstream electrode) was utilized to conduct the indirect amperometric detection. Bromide is oxidized to bromine at upstream electrode and reduced back to bromide at downstream electrode. Since taurine can react with bromine quantitatively and rapidly, its concentration can therefore be determined by the decrease of the current for bromine reduction at the downstream electrode. Principal experimental parameters governing the analytical performance were investigated and optimized. Under the optimal conditions, taurine can be baseline separated from interfering amino acids and the detection limit of 0.18 μM was obtained with a linear correlation coefficient of 0.999 over the concentration range of 0.5–60 μM. The developed method has been successfully applied in the determination of taurine in human tear fluid. The taurine level obtained was in good agreement with previous reports and recoveries for taurine spiked ranged from 92–95% with relative standard deviations within 4.6%, demonstrating the reliability of the developed method in the determination of taurine in human tear fluid. 相似文献