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81.
Revealing how a biological network is organized to realize its function is one of the main topics in systems biology. The functional backbone network, defined as the primary structure of the biological network, is of great importance in maintaining the main function of the biological network. We propose a new algorithm, the tinker algorithm, to determine this core structure and apply it in the cell-cycle system. With this algorithm, the backbone network of the cell-cycle network can be determined accurately and efficiently in various models such as the Boolean model, stochastic model, and ordinary differential equation model. Results show that our algorithm is more efficient than that used in the previous research. We hope this method can be put into practical use in relevant future studies. 相似文献
82.
83.
Electrochemistry methods were used to investigate the influence of pH on the passive film and corrosion behavior of ultrahigh strength AM355 stainless steel in chloride-containing media. Analysis of the Pourbaix diagram indicates that AM355 stainless steel exhibits higher corrosion resistance in natural and near-natural environments than that in acidic and alkaline conditions. Electrochemistry measurements and composition analysis of the passive film show that pitting potential increased due to the enhanced repassivation capacity of AM355 stainless steel with increasing pH. The mixed MnS/oxide inclusions are the main pitting sensitive locations under all conditions. Morphological observations and energy-dispersive spectroscopy showed that the influence of the gap between the martensitic laths is significant with increasing pH. The inclusions, element concentrations, and microstructures weaken the resistance of ultrahigh-strength martensitic AM355 stainless steel against corrosion. 相似文献
84.
85.
Fuxiao Lu Guowei Liu Jianxiong Zhang Wansheng Tang 《The Journal of the Operational Research Society》2016,67(10):1309-1324
Consider a bilateral monopoly supply chain where a manufacturer distributes a durable product through a retailer to end consumers. This paper develops a differential game in which the manufacturer determines the advertising and the wholesale price while the retailer sets the retail price. Channel members are partially myopic when they only consider goodwill dynamics and disregard sales evolution. We derive and compare partially myopic and forward-looking strategies with the following observations: First, under decentralized scenario, partially myopic channel members get higher profits than the forward-looking ones, while the opposite result occurs in centralized scenario. Second, when channel members are partially myopic, the distribution channel can benefit from the strategic decentralization. 相似文献
86.
tBu4NCl/K2S2O8 System Induced C-2 Functionalization of 8-Aminoquinoline Amides with Primary Alcohols
Kaixin Zhang Jianxiong Xu Jinxiang Xiao Prof. Ronglin Zhong Prof. Jizhen Li 《European journal of organic chemistry》2023,26(7):e202201432
A metal and light-free Minisci-type acylation approach of 8-aminoquinoline amides with general primary alcohols was demonstrated under tBu4NCl/K2S2O8 system. Simultaneously, the C2−H alkylation can be realized by accident for special benzyl alcohols bearing strong electron-donating groups. Most N-heterocycles were also compatible to afford corresponding acylated products. Furthermore, the mechanism investigation reveals that chlorine radical induced the original ketyl radical generation through abstracting the α-C−H from the alcohols, then underwent nucleophilic carbon-centered radicals addition, deprotonation, and oxidation to provide the target acylation products. 相似文献
87.
Jianxiong Chen Xiangyu Wang Xi Cui Yongyi Li Prof. Yuqi Feng Prof. Zhenwei Wei 《Angewandte Chemie (International ed. in English)》2023,62(12):e202219302
The in-depth study of electrochemical (EC) synthesis can require a powerful mass spectrometry (MS) analytical platform which can discover and identify fleeting intermediates in EC reactions. Here we report a floating electrolytic electrospray ionization (FE-ESI) strategy that can perform EC processes in a floating electrolytic cell and monitor intermediates by high-resolution MS. Compared with previous EC-MS methods, a significant advantage of FE-ESI-MS is that it allows one to modulate the electrolytic and electrospray process individually, ensuring its high sensitivity in discovering intermediates and universality to investigate redox reactions in different scenarios. This powerful platform has been successfully used to investigate the EC reductive coupling of p-tolylboronic acid and p-nitrotoluene. A series of nitrene intermediates were discovered and identified by FE-ESI-MS, indicating that a hidden mechanism involving nitrene formation might play a key role in EC reductive coupling process. 相似文献
88.
Jianxiong Xu Xin Xiao Yaoyao Zhang Wangqing Zhang Pingchuan Sun 《Journal of polymer science. Part A, Polymer chemistry》2013,51(5):1147-1161
The nonionic amphiphilic brush polymers such as poly[poly(ethylene oxide) methyl ether vinylphenyl‐co‐styrene] trithiocarbonate [P(mPEGV‐co‐St)‐TTC] and poly[poly(ethylene oxide) methyl ether vinylphenyl‐b‐styrene‐b‐poly(ethylene oxide) methyl ether vinylphenyl] trithiocarbonate [P(mPEGV‐b‐St‐b‐mPEGV)‐TTC] with different monomer sequence and chemical composition are synthesized and their application as macro‐RAFT agent in the emulsion RAFT polymerization of styrene is explored. It is found that the monomer sequence in the brush polymers exerts great influence on the emulsion RAFT polymerization kinetics, and the fast polymerization with short induction period in the presence of P(mPEGV‐co‐St)‐TTC is demonstrated. Besides, the chemical composition in the brush polymer macro‐RAFT agent effect on the emulsion RAFT polymerization is investigated, and the macro‐RAFT agent with high percent of the hydrophobic PS segment leads to fast and well controlled polymerization. The growth of triblock copolymer colloids in the emulsion polymerization is checked, and it reveals that the colloidal morphology is ascribed to the hydrophobic PS block extension, and the P(mPEGV‐co‐St) block almost have no influence just on the size of the colloids. This may be the first example to study the monomer sequence and the chemical composition in the macro‐RAFT agent on emulsion RAFT polymerization, and will be useful to reveal the block copolymer particle growth. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013 相似文献
89.
A series of polyurethane (PU) microencapsulated ammonium polyphosphate (MCAPP) were prepared by in situ polymerization from toluene‐2,4‐diisocyanate (TDI), polyethylene glycol (PEG), and pentaerythtritol (PER). And the structure was characterized by Fourier transform infrared spectroscopy (FTIR) and X‐ray photoelectron spectroscopy (XPS). Then it chose the optimal PEG constituent to design microcapsule from scanning electron microscopy (SEM) and water solubility test. The combustion and thermal degradation behaviors of PU blended APP or MCAPP were investigated by thermogravimetric analysis (TGA), UL‐94 test, and microcombustion calorimetry. The results showed that the PU/MCAPP had better thermal stability and flame retardance, due to the stable char forming by APP and PU shell. Moreover, the water resistance of flame retarded PU composite was greatly improved. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
90.
Hansheng Lian Enmin Feng Xiaofang Li Jianxiong Ye Zhilong Xiu 《Nonlinear Analysis: Real World Applications》2009,10(5):2749-2757
By introducing discrete time delay into the model for producing 1,3-propanediol by microbial continuous fermentation, we consider the stability and Hopf bifurcation of the delay differential system. Through numerical simulations, we get the rule of branch value changing with parameter and draw the pictures of periodic solutions and phase diagrams with specified parameters. The effect of time delay suggests that the system can qualitatively describe oscillatory phenomena occurring in the experiment. 相似文献