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41.
Jian Yang  Bo Gao  Wei Liu  Jiang Du  Prof. Qun Xu 《Chemphyschem》2023,24(10):e202200793
The realization of ferromagnetic ordering of two-dimensional (2D) carbon material graphdiyne (GDY) has attracted great attention due to its promising application in spin semiconductor devices. However, the absence of localized spins makes the pristine GDY intrinsically nonferromagnetic. Herein, we report the realization of robust room-temperature (RT) ferromagnetism (FM) with Curie temperature (TC) up to 325 K for GDY Nanosheets (GDYNs) by supercritical CO2 (SC CO2). Experimental and theoretical calculations reveal that the new chemical bond of C−O−Si can be formed because of the unique effect of SC CO2, which help to enhance the charge transfer and generates long-range ferromagnetic order. The RT saturation magnetization (MS) reaches 1.125 emu/g, which is much higher than that of carbon-based materials reported up to now. Meanwhile, by changing the conditions of SC CO2 such as pressure, ferromagnetic responses can be manipulated, which is great for potential spintronics applications of GDY.  相似文献   
42.
本文以国产滤纸为基质,醋酸汞作重原子微扰剂,详细研究了 RTP 的各种条件,成功地建立了测定核黄素的纸基质室温燐光法(PS-RTP)。结果表明,核黄素标准曲线线性范围为5×10~(-6)~1×10~(-3)mol/L,检出限为0.75ng。将该法用于血清中核黄素的测定,标准回收率在93.5%~103%之间。  相似文献   
43.
白小红  魏雁声  刘长松 《分析化学》1999,27(11):1292-1295
在β-环糊精溶液中,环氧溴丙烷(EBH)或环氧氯烷(ECH)能够诱导α-溴代萘(α-BrN)和β-溴代萘(β-BrN)强的室温燐光(RTP).结果证明,EBH比ECH有更强的重原子增强效应(HAEE);α-BrN/ECH/β-CD三元包接合物的稳定性比β-BrN/ECH/β-CD稳定性更强.  相似文献   
44.
随着纳米技术的发展,结合了纳米技术与材料制备技术而发展起来的荧光染料嵌合的核壳荧光纳米颗粒的制备为生物医学领域的研究提供了新的材料、技术和方法。何晓晓等以联钉吡啶配合物为核材料,制备了嵌合无机金属配合物的核壳荧光纳米颗粒,段菁华等用异硫氰酸荧光素FITC与蛋白质IgG相结合,  相似文献   
45.
《化学:亚洲杂志》2018,13(19):2770-2780
Owing to resource abundance, and hence, a reduction in cost, wider global distribution, environmental benignity, and sustainability, sodium‐based, rechargeable batteries are believed to be the most feasible and enthralling energy‐storage devices. Accordingly, they have recently attracted attention from both the scientific and industrial communities. However, to compete with and exceed dominating lithium‐ion technologies, breakthrough research is urgently needed. Among all non‐electrode components of the sodium‐based battery system, the electrolyte is considered to be the most critical element, and its tailored design and formulation is of top priority. The incorporation of a small dose of foreign molecules, called additives, brings vast, salient benefits to the electrolytes. Thus, this review presents progress in electrolyte additives for room‐temperature, sodium‐based, rechargeable batteries, by enlisting sodium‐ion, Na−O2/air, Na−S, and sodium‐intercalated cathode type‐based batteries.  相似文献   
46.
General Stochastic Hybrid System (SHS) are characterised by Stochastic Differential Equations (SDEs) with discontinuities and Poisson jump processes. SHS are useful in model based design of Cyber-Physical System (CPS) controllers under uncertainty. Industry standard model based design tools such as Simulink/Stateflow® are inefficient when simulating, testing, and validating SHS, because of dependence on fixed-step Euler–Maruyama (EM) integration and discontinuity detection. We present a novel efficient adaptive step-size simulation/integration technique for general SHSs modelled as a network of Stochastic Hybrid Automatons (SHAs). We propose a simulation algorithm where each SHA in the network executes synchronously with the other, at an integration step-size computed using adaptive step-size integration. Ito’ multi-dimensional lemma and the inverse sampling theorem are leveraged to compute the integration step-size by making the SDEs and Poisson jump rate integration dependent upon discontinuities. Existence and convergence analysis along with experimental results show that the proposed technique is substantially faster than Simulink/Stateflow®when simulating general SHSs.  相似文献   
47.
采用同步镀铋膜法修饰玻碳电极及差分脉冲溶出伏安法测试土壤中Cr。在优化的实验条件下,以KNO3为支持电解质,NaAc-HAc(pH=5.5)为缓冲溶液的铋膜上得到Cr溶出特征峰电位为-1.14V,线性方程为:I=0.0747C+0.31054,相关系数为0.9981,检出限为0.001μg/L,线性范围为0.01—60μg/L,RSD=2.47%,该方法简单快速,准确度和精密度均符合要求,回收率为96.7%—104.5%。  相似文献   
48.
在碱性条件下水解正硅酸乙酯(TEOS)制备纳米二氧化硅(SiO_2)粒子,并采用同步荧光光谱和紫外可见分光光度法探讨了SiO_2对牛血清白蛋白(Bovine Serum Albumin,BSA)结构的影响。结果显示,SiO_2纳米粒子对BSA的结构没有发生显著的影响,这说明在实验条件下,SiO_2不会改变BSA分子的结构和微环境。  相似文献   
49.
Luminescent 50-nm silicon dioxide nanoparticles containing both types of rhodamine 6G (R; particles denoted R-SiO2) were synthesized by the sol–gel method. In the presence of Pb(Ac)2 as a heavy atom perturber the particle can emit the intense and stable room-temperature phosphorescence (RTP) signal of R on a polyamide membrane, with exmax/emmax=470/635 nm for R. Our research indicates that the specific immune reaction between goat-anti-human IgG antibody labeled with R-SiO2 and human IgG can be carried out quantitatively on a polyamide membrane, and the phosphorescence intensity was enhanced after the immunoreaction. Thus a new method for solid-substrate room-temperature phosphorescence immunoassay (SS-RTP-IA) for determination of human IgG was established on the basis of antibody labeled with the nanoparticles containing binary luminescent molecules. The linear range of this method is 0.0624–20.0 pg spot–1 of human IgG (corresponding to a concentration range of 0.156–50.0 ng mL–1, sample volume 0.40 L spot–1). The regression equations of the working curves are Ip=71.27+7.208mIgG (pg spot–1) (r=0.9996). Detection limits calculated as 3Sb/k are 0.022 pg spot–1. Compared with the same IA using fluorescein isothiocyanate (FITC) as the marker the new method was more sensitive and had a wider linear range. After elevenfold replicate measurement RSD are 4.5 and 3.6% for samples containing 0.156 and 50.0 ng mL–1 IgG, respectively. This method is sensitive, accurate, and of high precision.  相似文献   
50.
利用溶胶-凝胶法制备了ZrO2/SiO2纳米复合物室温磷光材料,通过各条件的优化,最终确定溶剂为异丙醇、Zr摩尔掺杂百分含量为15%、550℃下煅烧3h得到的纳米ZrO2/SiO2复合物的室温磷光发光性能较好,其最大激发波长为280nm、发射波长为460nm,且磷光寿命为0.56s。  相似文献   
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