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131.
132.
药物甲氧苄氨嘧啶分子模板聚合物
结合作用及选择性研究 总被引:4,自引:0,他引:4
采用分子自组装印迹技术合成了对甲氧苄氨嘧啶有高选择性的模板聚合物受体.通过Scatchard分析、 相似文献
133.
Two novel borophosphates, MII(C4H12N2)[B2P3O12(OH)] (MII = Co, Zn), exhibiting open frameworks, have been synthesized by hydrothermal reactions (T = 165 °C). The crystal structures of the isotypic compounds have been determined both at 293 K (orthorhombic, Ima2 (no. 46), Z = 4; MII = Co: a = 12.4635(4) Å, b = 9.4021(4) Å, c = 11.4513(5) Å, V = 1341.90 Å3, R1 = 0.0202, wR2 = 0.0452, 2225 observed reflections with I > 2σ(I); MII = Zn: a = 12.4110(9) Å, b = 9.4550(5) Å, c = 11.4592(4) Å, V = 1344.69 Å3, R1 = 0.0621, wR2 = 0.0926, 1497 observed reflections with I > 2σ(I)). Distorted CoO6‐octahedra and ZnO5‐square‐pyramids, respectively, share common oxygen‐corners with BO4‐, PO4‐ and (HO)PO3‐tetrahedra. The tetrahedral groups are linked via common corners to form infinite loop‐branched borophosphate chains [B2P3O12(OH)4–]. The open framework of MII‐coordination polyhedra and tetrahedral borophosphate chains contains a three‐dimensional system of interconnected structural channels running along [100], [011] and [011], respectively, which are occupied by di‐protonated piperazinium ions. 相似文献
134.
Manfred Mutter Stphane Vuilleumier 《Angewandte Chemie (International ed. in English)》1989,28(5):535-554
Advances in methodology in both chemistry and molecular biology allow us to take a fresh look at protein science. Chemical synthesis of peptides and site-directed mutagenesis are now standard research tools, paving the way for the construction of new proteins with tailor-made structural and functional properties. The decisive hurdle on the way lies not in the synthesis of the molecules proper but rather in a better understanding of the complex folding pathways of polypeptide chains into spatially well-defined structures. Can the chemist use his synthetic tools to bypass the notorious “folding problem?” In this article, we present a new approach developed in our laboratory, which opens a chemical route to artificial proteins with predetermined three-dimensional structures, allowing a first step towards the synthesis of new proteins with functional properties. 相似文献
135.
以金属凝胶纤维为模板制备环境响应型共聚物一维纳米结构 总被引:1,自引:0,他引:1
分别以4-乙烯基吡啶(4VP)、丙烯酸(AAc)和N-异丙基丙烯酰胺(NIPAM)为共聚单体,以金属凝胶纤维为模板,通过自由基共聚合得到了具有环境响应性的共聚物一维纳米结构.采用红外光谱(FTIR)、流变仪和透射电子显微镜(TEM)等表征了共聚物一维纳米结构的组成、强度及微观形貌.结果表明,共聚单体与模板的配位能力强弱对所得到的共聚物一维纳米结构的产率、强度和形貌有很重要的影响.3种共聚物都具有相应的p H响应性和温度响应性,并且共聚单体含量越高,响应性越明显. 相似文献
136.
137.
3D gold brush nanoelectrode ensembles (BNEEs) consisted of gold nanowires 100 nm in diameter and 300 nm in length were fabricated by combining the technologies of template synthesis and controlled chemical etching of the membrane. The structure and morphology of the BNEEs was imaged by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The real active areas of BNEEs were found to be different when characterized by different redox species. The direct redox of daunorubicin (DNR) at the gold BNEEs exhibited absorption‐controlled characteristics and high current activity. BNEEs are reliable and effective in DNR detection. 相似文献
138.
Nicholas N. Bwana 《Journal of nanoparticle research》2008,10(2):313-319
Highly ordered anodic alumina was produced, on RF sputtered aluminium on a conductive glass substrate, by two step anodizing
process in 0.4 M sulphuric acid at constant cell potentials of between 5 and 25 V and at a constant current density of 20 mA
cm−2. The temperature was kept constant at 15 °C during both anodization processes. The effects of the anodizing potential, current
density, and time on the pore diameters were established. Longer anodization periods result in wider irregular pores with
reduced porosity for both constant potential and constant current density anodization processes. The current density increases
with increasing constant anodizing potential and generally remains constant with time after a sharp rise. Potential drop during
constant current density anodization behaves in a similar manner. We confirm that sulphuric acid has a self-ordering potential
of 25 V above which burning occurs. 相似文献
139.
模板法制备枝状Pt纳米线 总被引:10,自引:2,他引:8
一维纳米材料的制备是近年来纳米材料的研究热点. 利用具有纳米尺度的孔洞阵列模板沉积各种材料构筑纳米线的方法具有制备简便和成本较低等优点[1,2]. 常用的模板有多孔阳极氧化铝(AAO)、多孔硅和聚合物等, 其中AAO模板具有耐高温, 绝缘性好, 孔洞分布均匀, 孔径、孔深大小可控等特点, 是模板法研究的热点. 通过模板法电化学沉积制备各种金属纳米线已有很多报道[3~8], 本研究小组也曾报道了模板法电化学沉积Au等纳米线的制备及性质[9~12], 但用该方法制备的金属纳米线都为单一的线状结构. 组成当代大规模集成电路的基本器件一般具有3个或3个以上的电极. 单一的线状结构纳米线, 不能满足纳米电子学对纳米材料和纳米器件性能研究的需要. 在纳米器件的特性研究和探索中, 枝状或Y形纳米结的制备有重要的意义, 它是纳米器件从理论到实用化的必备条件. Sui等[13]用模板法成功制备了枝状碳纳米管, 但用AAO模板制备枝状金属纳米线的研究至今还未见报道. 本文通过控制铝片的阳极氧化条件, 先制备出具有分枝状孔洞结构的AAO模板, 再用电化学法沉积金属Pt, 实现了枝状Pt纳米线的可控生长. 这对其它金属枝状纳米线的制备以及进一步掺杂、构筑纳米原型器件等具有显著的实用价值. 相似文献
140.
The use of electron radiation is an effective tool for stimulating a controlled modification of structural and conductive properties of nanomaterials in modern materials science. The paper presents the results of studies of the influence of various types of radiation on structural and conductive properties of copper nanotubes obtained by electrochemical synthesis in pores of templates based on polyethylene terephthalate. Such methods as SEM, X-ray diffraction and EDS show that irradiation with a stream of high-energy electrons with doses of 50–250 kGy makes it possible to modify the crystal structure of nanotubes, increasing their conductivity and decreasing the resistance of nanostructures without destroying the structure. 相似文献