全文获取类型
收费全文 | 81篇 |
免费 | 5篇 |
国内免费 | 10篇 |
专业分类
化学 | 54篇 |
晶体学 | 3篇 |
力学 | 1篇 |
数学 | 29篇 |
物理学 | 9篇 |
出版年
2023年 | 4篇 |
2021年 | 2篇 |
2020年 | 3篇 |
2019年 | 10篇 |
2018年 | 4篇 |
2017年 | 4篇 |
2016年 | 3篇 |
2015年 | 5篇 |
2014年 | 1篇 |
2013年 | 5篇 |
2012年 | 8篇 |
2011年 | 2篇 |
2010年 | 5篇 |
2009年 | 1篇 |
2008年 | 5篇 |
2007年 | 6篇 |
2006年 | 2篇 |
2005年 | 2篇 |
2004年 | 1篇 |
2003年 | 4篇 |
2002年 | 3篇 |
2000年 | 1篇 |
1999年 | 1篇 |
1996年 | 3篇 |
1994年 | 2篇 |
1993年 | 3篇 |
1992年 | 1篇 |
1991年 | 2篇 |
1990年 | 2篇 |
1981年 | 1篇 |
排序方式: 共有96条查询结果,搜索用时 140 毫秒
21.
Tang Peixin Lockett Leilah-Marie E. Zhang Mengxiao Sun Gang 《Cellulose (London, England)》2021,28(10):6699-6712
Cellulose - A chemical modification of cotton fabrics by 2-diethylaminoethyl chloride (DEAE-Cl) was achieved, and the resulted cotton fabrics demonstrated salt-free dyeing properties with anionic... 相似文献
22.
Li Jingwen Liu Xiaolong Cui Peixin Li Junmeng Ye Tao Wang Xi Zhang Chuang Zhao Yong Sheng 《中国科学:化学(英文版)》2019,62(9):1257-1262
The structural flexibility of hybrid perovskite materials allows for phase transition and consequently thermochromic properties.Here we investigate the thermochromic performance in a series of copper-based layered perovskites with organic cations having different alky chain lengths. Their transition temperature is found to be dependent on the organic cations due to molecular motion and hydrogen bond interaction, providing possibilities to prepare thermochromic semiconductors near room temperature for smart window applications. 相似文献
23.
如果中央空调制冷实验设备中水泵选择不当,会使系统运行不正常,或者导致能量消耗加大,这都将造成工程的失败,因此,合理选择循环水泵具有重要的意义。以某中央空调制冷实验设备设计为例,说明水泵的合理选择方法。其对中央空调设计具有一定的参考价值。 相似文献
24.
Global classical solution to the 3D isentropic compressible Navier–Stokes equations with general initial data and a density‐dependent viscosity coefficient 下载免费PDF全文
Peixin Zhang 《Mathematical Methods in the Applied Sciences》2015,38(6):1158-1177
In this paper, we study the global existence of classical solutions to the three‐dimensional compressible Navier–Stokes equations with a density‐dependent viscosity coefficient (λ = λ(ρ)). For the general initial data, which could be either vacuum or non‐vacuum, we prove the global existence of classical solutions, under the assumption that the viscosity coefficient μ is large enough. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
25.
We study the approximation of functions from anisotropic Sobolev classes B(Wrp([0,1]d)) and Hölder-Nikolskii classes B(Hrp([0,1]d)) in the Lq([0,1]d) norm with q ≤ p in the quantum model of computation. We determine the quantum query complexity of this problem up to logarithmic factors. It shows that the quantum algorithms are significantly better than the classical deterministic or randomized algorithms. 相似文献
26.
Zhang Chenle Deng Libo Zhang Peixin Ren Xiangzhong Li Yongliang He Tingshu 《Journal of Solid State Electrochemistry》2017,21(12):3579-3588
Journal of Solid State Electrochemistry - The performance of dye-sensitized solar cells (DSSCs) is critically dependent on the catalytic activity of their counter electrode (CE) materials. There... 相似文献
27.
28.
An amphiphilic graft copolymer poly(vinyl alcohol)-g-poly(butyl acrylate) (PVA-g-PBA) was synthesized by grafting butyl acrylate (BA) onto poly(vinyl alcohol) (PVA) with potassium persulfate (KPS) as free radical initiator in N2 atmosphere and aqueous medium. The formation of graft copolymer was confirmed by means of infrared spectroscopy (IR). The influences of initiator, monomer concentration and reaction time on the percentage of monomer conversion(C M), graft degree(Gd) and graft efficiency(Ge) have been discussed in detail. PVA-g-PBA was used as compatibilizer in blends of chlorinated polyethylene (CPE)/ poly(acrylic acid-co-acrylamide)[P(AA-AM)], and the compatibility between CPE and P(AA-AM) was also investigated. 相似文献
29.
The main goal of this paper is to understand which properties of a basis are important for certain direct and inverse theorems
in nonlinear approximation. We study greedy approximation with regard to bases with different properties. We consider bases
that are tensor products of univariate greedy bases. Some results known for unconditional bases are extended to the case of
quasi-greedy bases. 相似文献
30.
根据YBa_2Cu_3O_(7-δ)超导定向膜经不同温度退火后的红外反射光谱和不同掺Zn量的YBa_2Cu_(3-z)Zn_xO_(7-δ)的红外吸收光谱在500-700厘米~(-1)特征峰的变化,进一步讨论了YBa_2Cu_3O_(7-δ)中Ba-Ba层间和Y-Ba层间Cu-O键伸缩振动的三个红外吸收峰强度变化的本质。用红外入射光穿透深度随Y系样品电阻率提高而增大和对应二维CuO_2网络中Cu-O反称振动吸收的590厘米~(-1)峰强度变化不受氧缺位影响的事实,说明590厘米~(-1)的吸收峰不是氧缺位诱导的准局域振动模。同时对620厘米~(-1)和550厘米~(-1)吸收峰的解释也给予了必要的补充和验证。 相似文献