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241.
In this paper, we have used the hydrogen-bonding interactions, combining the designed diamine ligands and anionic metal chlorides, into the construction of a series of new pillar-layered supramolecular complexes. The flexible molecule N,N,N′,N′-tetra-p-methoxybenzyl-ethylenediamine (L1) bearing doubly protonated H-bond donors, has been synthesized and reacted with the metal chlorides (such as [PdCl4]2?, [FeCl4]? and [CoCl4]2?) via weak C–H···Cl interactions, yielding crystal products [H2 L1]2+·Cl?·[FeCl4]? (1), 0.5H2O ? [H2 L1]2+·Cl?·0.5[PdCl4]2? (2) and [2-hydroxy naphthyl]1.5 ? 2[H2 L1]2+·2Cl?·[CoCl4]2? (3). The 3-D networks are organic double layers formed by the self-assembly of the ligands through extensive hydrogen-bonding interactions (C–H···O or C–H···π interactions) and further interconnected by [PdCl4]2?/[FeCl4]?/[CoCl4]2? in a pillar fashion, constructing into pillar-layered networks with channels accessible to various guest molecules. The inclusion property of [H2 L1][CoCl4] was studied, varieties of guest molecules, such as 2-hydroxy naphthyl, phenanthrene and hydroquinone, can be included in the framework.  相似文献   
242.
制备了一种以邻二氮菲合铁配离子与γ-氨基丁酸形成的缔合物为电活性物的γ-氨基丁酸碳糊电极,并对其性能做了测定。结果显示该电极对γ-氨基丁酸有较好的能斯特响应。γ-氨基丁酸的线性范围为1.0×10-5~8.0×10-2 mol.L-1,极差电位为38mV.pc-1,测定下限(10S/N)为5.2×10-6 mol.L-1。电极用于糙米、青稞籽和茶叶中γ-氨基丁酸含量的测定,结果与分光光度法结果相符。  相似文献   
243.
利用沸石前驱体溶液和介孔硅球(MSS)为原料, 通过水热法成功制备了具有中强酸性介孔壳的中空介孔硅铝球形分子筛(HMAS)。利用透射电镜(TEM)、扫描电镜(SEM)、X射线衍射(XRD)、N2-吸脱附、27Al核磁共振(27Al NMR)及NH3程序升温脱附(NH3-TPD)对材料的结构和性能进行了表征。研究结果表明, 在MSS的中空过程中伴随有物质再分配和介孔结构的逐渐演变。MSS介孔孔道中的十六烷基三甲基溴化铵(CTAB)分子, 一方面保护MSS免遭强碱性沸石前驱体溶液的溶蚀, 另一方面作为形成HMAS介孔壳层的模板剂。在此CTAB分子的作用下, 沸石前驱体结构单元被引入到HMAS的介孔球壳上。所得材料具有介孔结构和中强酸性, 在催化裂解1, 3, 5-三异丙苯反应中表现出优异的催化性能。  相似文献   
244.
A facile,efficient synthesis of 3-(guaiazulen-1-yl)succinimides was developed by Michael-type addition of guaiazulene to maleimides in the presence of p-toluenesulfonic acid under mild reaction conditions.  相似文献   
245.
The nonadiabatic effects in the molecular high-order harmonic generation (MHHG) from H2+ and its isotope have been theoretically investigated beyond the Born-Oppenheimer approximations. It is found that (i) due to the asymmetric contributions of the harmonic emission on the rising and the falling parts of the laser field, the frequency red-shifts in the MHHG can be found. As the initial vibrational state or the pulse intensity increases, the red-shifts of the harmonics are decreased and even the blue-shifts of the harmonics can be found in the higher pulse intensity with the higher vibrational state. With the increase of the pulse duration, the frequency red-shifts and the blue-shifts in the MHHG are decreased and enhanced, respectively. The shifts of the harmonics from the heavy nuclei are decreased compared with those from the light nuclei. (ii) Due to the coupling of the electron-nuclear dynamics, the non-odd harmonics can be produced at the larger internuclear distance. With the increase of the initial vibrational state or the pulse duration, the generations of the non-odd harmonics can be enhanced. As the pulse intensity increases, the intensities of the non-odd harmonics are first increased and then decreased at the much larger pulse intensity. Due to the slower nuclear motion, the generations of the non-odd harmonics are decreased as the nuclear mass increases. (iii) With the increase of the alignment angle of the molecule ions, the nonadiabatic effects in MHHG (including the shifts of the harmonics and the generations of the non-odd harmonics) are decreased.  相似文献   
246.
Hydrochloric Tramadol is a safe effective and not addictive emollient, the methods to gauge the quantity of it are Ultraviolet Spectrophotometry,HPLC, Gas Chromatography-Mass Spectrometry and so on.  相似文献   
247.
报道了一种以曲马多碘化物与碘化铋的分子缔合物为电活性物的新型全固态选择电极,电极的能斯特响应范围为6.3×10~(-2)~3.2×10~(-5)mol·L~(-1),斜率为50mV/pC,检测限为0.6×10~(-5)mol·L~(-1)。此电极响应迅速,重现性好。用此电极以标准曲线法对注射液中的曲马多进行了测定,结果与紫外分光光度法相符。  相似文献   
248.
Terminalia chebula Retz. forms a key component of traditional folk medicine and is also reported to possess antihepatitis C virus (HCV) and immunomodulatory activities. However, information on the intermolecular interactions of phytochemicals from this plant with HCV and human proteins are yet to be established. Thus, by this current study, we investigated the HCV NS3/4A inhibitory and host immune-modulatory activity of phytocompounds from T. chebula through in silico strategies involving network pharmacology and structural bioinformatics techniques. To start with, the phytochemical dataset of T. chebula was curated from biological databases and the published literature. Further, the target ability of the phytocompounds was predicted using BindingDB for both HCV NS3/4A and other probable host targets involved in the immune system. Further, the identified targets were docked to the phytochemical dataset using AutoDock Vina executed through the POAP pipeline. The resultant docked complexes with significant binding energy were subjected to 50 ns molecular dynamics (MD) simulation in order to infer the stability of complex formation. During network pharmacology analysis, the gene set pathway enrichment of host targets was performed using the STRING and Reactome pathway databases. Further, the biological network among compounds, proteins, and pathways was constructed using Cytoscape 3.6.1. Furthermore, the druglikeness, side effects, and toxicity of the phytocompounds were also predicted using the MolSoft, ADVERpred, and PreADMET methods, respectively. Out of 41 selected compounds, 10 were predicted to target HCV NS3/4A and also to possess druglike and nontoxic properties. Among these 10 molecules, Chebulagic acid and 1,2,3,4,6-Pentagalloyl glucose exhibited potent HCV NS3/4A inhibitory activity, as these scored a lowest binding energy (BE) of −8.6 kcal/mol and −7.7 kcal/mol with 11 and 20 intermolecular interactions with active site residues, respectively. These findings are highly comparable with Asunaprevir (known inhibitor of HCV NS3/4A), which scored a BE of −7.4 kcal/mol with 20 key intermolecular interactions. MD studies also strongly suggest that chebulagic acid and 1,2,3,4,6-Pentagalloyl glucose as promising leads, as these molecules showed stable binding during 50 ns of production run. Further, the gene set enrichment and network analysis of 18 protein targets prioritized 10 compounds and were predicted to potentially modulate the host immune system, hemostasis, cytokine levels, interleukins signaling pathways, and platelet aggregation. On overall analysis, this present study predicts that tannins from T. chebula have a potential HCV NS3/4A inhibitory and host immune-modulatory activity. However, further experimental studies are required to confirm the efficacies.  相似文献   
249.
为了研究天然气水合物开采过程中水合物饱和度和有效应力变化对含水合物沉积层渗透率变化规律的影响,利用自主研制的水合物沉积物合成与三轴渗流实验一体化装置,进行了有效应力升降过程中不同饱和度水合物沉积物渗透性实验。结果表明:有效应力升降过程中,不同饱和度水合物沉积物的渗透率与有效应力均呈负指数规律变化,并表现出在低有效应力阶段渗透率变化的幅度大于高有效应力阶段;有效应力升降过程中,试样产生的不可恢复变形使渗透率不能完全恢复,造成渗透率永久损失;有效应力不变时,水合物沉积物的渗透率与水合物饱和度呈负指数规律变化,且曲线的斜率随饱和度增加由大变小;水合物的饱和度越大,最大渗透率损害率越大,渗透率恢复的程度越差。  相似文献   
250.
吴宪龙  朱爱丽 《色谱》1998,16(6):536-538
采用PhenomenexSpherexC18色谱柱,以含50mmol/L乙酸-乙酸钠缓冲溶液(pH6.0)的V(乙腈)∶V(乙醚)∶V(水)=12∶10∶78混合溶液为流动相,用分光光度法检测,检测波长为275nm,在16min内实现了4,4′-二氨基联苯、4-硝基酚和苯酚的同时分离测定。检测限分别为0.14,0.19和0.08ng。标准回收率分别为98.85%,98.15%和98.10%。方法灵敏度高,用于环境水样分析时结果令人满意。  相似文献   
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