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61.
Aysun apc Mlanie M. Lorion Hui Wang Nina Simon Maria Leidenberger Mariana C. BorgesSilva Diogo R. M. Moreira Yongping Zhu Yuqing Meng Jia Yun Chen Yew Mun Lee Oliver Friedrich Barbara Kappes Jigang Wang Lutz Ackermann Svetlana B. Tsogoeva 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(37):13295-13295
62.
Dr. Wei Wen Tan Yew Jin Ong Prof. Naohiko Yoshikai 《Angewandte Chemie (International ed. in English)》2017,56(28):8240-8244
A copper-catalyzed condensation reaction of oxime acetates and α,β-unsaturated ketimines to give pyridine derivatives is reported. The reaction features mild conditions, high functional-group compatibility, and high regioselectivity with respect to unsymmetrical oxime acetates, thus allowing the preparation of a wide range of polysubstituted pyridines, many of which are not readily accessible by conventional condensation methods. 相似文献
63.
Biswanath Das Gurram Mahender YerraKoteswara Rao Chimmani Ramesh Katta Venkateswarlu Krishnan Ravikumar Madamanchi Geethangili Yew‐Min Tzeng 《Helvetica chimica acta》2006,89(2):285-290
Two new pseudoguaianolide‐type sesquiterpene lactones, named deacetyltetraneurin A ( 3 ) and hysterone E ( 4 ), were isolated from flowers of the plant Parthenium hysterophorus L., along with the seven known compounds parthenin ( 1 ), coronopilin, tetraneurin A, 8‐β‐hydroxycoronopilin, scopoletin, hysterone D, and conchasin A ( 2 ). The structures of all the compounds were deduced by means of elemental analysis and extensive spectroscopic (1D and 2D NMR) studies, and confirmed for 3 and 4 by X‐ray crystallographic analysis. 相似文献
64.
Colin J.R. Sheppard Shakil Rehman Naveen K. Balla Elijah Y.S. Yew 《Optics Communications》2009,282(24):4647-24077
An approximation to a Bessel beam produced by tightly focusing linearly polarized light is known to produce a smaller central lobe than focusing plane polarized light. This is because the plane polarized wave gives a broad central lobe caused mainly by a parasitic longitudinal field component. It is known that this problem can be overcome by focusing radially polarized light. Here we demonstrate that other polarization distributions based on a linear combination of transverse electric (TE1) and transverse magnetic (TM1) fields can give a beam even narrower than for the radially polarized case. Special cases of this combination are identified, corresponding to the smallest width (TE1), and the maximum peak intensity compared with the side lobes (electric dipole polarization). Axially-symmetric forms can be generated by illumination with elliptically polarized light. A particular case is azimuthal polarization with a phase singularity, which is equivalent to TE1. For a semi-angular aperture of 60°, the TE1 case gives a central lobe width 9% narrower than for radially polarized illumination, while for plane polarized illumination it is 12% wider than the radially polarized case. 相似文献
65.
We study the problem of allocating a limited quantity of a single manufacturing resource to produce a subset of possible part-types. Customer orders require one or more part-types. We assume that revenue is received for an order only if it is completely filled, and that set-up costs and order revenues dominate the variable costs of production. We present a heuristic for the solution of our problem, as well as families of cutting-planes for an integer programming formulation. Computational results on a set of random test problems indicate that the heuristic is quite effective in producing near optimal solutions. The cutting-planes appear to be quite useful in reducing the number of linear programming solutions required by branch-and-bound. 相似文献
66.
Morteza Lalmazloumian Kuan Yew Wong Kannan Govindan Devika Kannan 《Annals of Operations Research》2016,240(2):435-470
Supply chain planning as one of the most important processes within the supply chain management concept, has a great impact on firms’ success or failure. This paper considers a supply chain planning problem of an agile manufacturing company operating in a build-to-order environment under various kinds of uncertainty. An integrated optimization approach of procurement, production and distribution costs associated with the supply chain members has been taken into account. A robust optimization scenario-based approach is used to absorb the influence of uncertain parameters and variables. The formulation is a robust optimization model with the objective of minimizing the expected total supply chain cost while maintaining customer service level. The developed multi-product, multi-period, multi-echelon robust mixed-integer linear programming model is then solved using the CPLEX optimization studio and guidance related to future areas of research is given. 相似文献
67.
68.
P.Y.M. Yew D.D. Zhu Q.Y. Lin L. Jiang P.L. Chee H.S. Leong Z. Dong X.D. Guo D. Kai X.J. Loh 《Materials Today Chemistry》2021
There are various concerns with current sunscreen actives in the sun care industry which pushes for a natural-based active that is sustainable as well as effective. Lignin is a natural polymer, capable of ultraviolet (UV) filtration and maintaining photostability. In this study, a variety of tuneable lignin-poly(ethylene glycol) (LP) nanodiamond (LP–ND) complexes were developed with varying ratios of LP to NDs. There are two fractions of LP–NDs, which use detonation NDs (LP–rNDs) and furnace NDs (LP–mNDs). Both complexes demonstrated favorable UV filtration, enhanced photostability, and uniform dispersion in water and cream. The LP–mND had maintained its particle size at <200 nm with an increasing LP ratio from 0.5 to 20 times as opposed to the increased particle size of the LP–rND. The LP–mND complex excelled in its photostability during solar radiation from 1 h to 6 h, demonstrating its effectiveness in absorbing 70% in the UV B region. Results had indicated enhanced synergistic effect of LP–rNDs and LP–mNDs with commercial sunscreen. The LP–rND complex had enhanced the sunscreen from 29 to 62, whereas the LP–mND had further boosted the sun protection factor to 89. In a nutshell, the lignin nanodiamond complexes offer a sustainable alternative to current actives in the industry. 相似文献
69.
Protein microarray offers a means for high-throughput profiling of cellular proteins to provide insights into the mechanisms of biological processes. This study describes the design and fabrication of a robust platform, spatially addressable protein array (SAPA), by exploring the specificity of ssDNA hybridization for self-assembly of semi-synthetic ssDNA-antibody conjugates which capture antigens from complex biological samples. This approach does not involve the direct immobilization of antibodies nor antigen, but instead captures the target antigens in the solution phase followed by self-directed assembly of the complex onto the surface. In an effort to optimize the platform, the effects of surface chemistry, nonspecific protein adsorption, facile preparation, and purification of ssDNA-conjugated antibody and capture of the antigen from a complex biological sample such as cell lysate were examined. This platform allowed antigen detection in cell lysate with high sensitivity (1 pM). The method described herein can be extended to the high-throughput detection of other interacting molecules in solution phase and their subsequent assembly onto any substrate. 相似文献
70.
Yew Keong Choong Su-Qin SunQun Zhou Zakiah IsmailBadrul Amini Abdul Rashid Jia-Xun Tao 《Vibrational Spectroscopy》2011,57(1):87-96
In this paper, the feasibility and advantage of employing FTIR spectroscopy and the corresponding second-derivative spectroscopy combined with 2D-IR spectroscopy for the analysis of water extracts of Ganoderma lucidum with different storage durations were investigated and demonstrated for the first time. In order to compare the second-derivative microscopic fingerprint spectra from the four periods of storage, the range from 1200 to 500 cm−1 has to be ignored due to the detection of starch in the samples and the standard as well. This is crucial because the main characteristic band of polysaccharide was assigned within this range. The addition of starch as outer constituent was considered spoilage of polysaccharide content investigation. In fact, polysaccharide content in G. lucidum plays a main role as anti-cancer properties. The ranges from 1480 to 1200 cm−1 and from 1700 to 1480 cm−1 were interpreted and directly compared. For the range (from 1800 to 400 cm−1), the 22 months sample was closest to the control, followed by 38 months, 13 months and 6 months product. The matching of the extract spectra with the control was not consistent and depended on which range of spectra had been chosen. Many factors can be considered which may have possibly affected inferences of the composition of the extract from different storage durations. 相似文献