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21.
合成了3种主链含己烷雌酚的生物可降解的聚磷酸酯,结构经IR,^1HNMR和元素分析鉴定,通过水接触角的测定研究了聚合物的亲水-疏水性能,以pH值变化表征了聚合物的体外水解速率。初步的体外实验表明,此类聚磷酸酯具有较好的体外抗艾氏腹水癌活性。 相似文献
22.
The thermodynamic properties of saturated aqueous lanthanide nitrate solutions were determined using recently published critically evaluated solubility and activity data. The variation of the thermodynamic functions and congruent melting points as a function of atomic number are interpreted in terms of changes in inner sphere coordination number in both the solid hexahydrates and in the aquo ions, and in terms of the double-double effect.Inconsistencies in experimental solubility data are generally caused by uncertainties in solid phase composition which is shown to be due to the very small Gibbs energies accompanying transitions from stable to metastable systems differing in the number of hydrating water molecules.Presentation to First International Symposium on Solubility Phenomena, University of Western Ontario, London, Ontario, August 21–23, 1984. 相似文献
23.
Natalia V. Loginova Tat’yana V. Koval’chuk Rimma A. Zheldakova Anna A. Chernyavskaya Nikolai P. Osipovich Gennady K. Glushonok Henry I. Polozov Victor L. Sorokin Oleg I. Shadyro 《Central European Journal of Chemistry》2006,4(3):440-457
Cu (II) complexes with the sterically hindered diphenol derivatives 3,5-di(tert-butyl)-1,2-benzenediol (I), 4,6-di(tert-butyl)-1,2,3-benzenetriol (II) and the sulfur-containing 4,6-di(tert-butyl)-3-(2-hydroxyethylsulfanyl)-1,2-benzenediol (III) and 2-[4,6-di(tert-butyl)-2,3-dihydroxyphenylsulfanyl]acetic acid (IV) have been synthesized and characterized by elemental analysis, TG/DTA, FT-IR, ESR, XPS, XPD and conductivity measurements.
Compounds I–III can coordinate in their singly deprotonated forms and act as bidentate ligands. These compounds yield Cu (II) complexes of the stoichiometry Cu(L)2, which have square planar geometry (g| > g⊥ > ge). Unlike them, compound IV behaves as a terdentate ligand, and its complex Cu(LIV)2 has distorted octahedral geometry. According to ESR data, only the Cu(LII)2 complex contains a very small amount of phenoxyl radicals. Antimicrobial activities of these ligands and their respective
Cu (II) complexes have been determined with respect to Gram-positive and Gram-negative bacteria, as well as on yeasts. Their
phytotoxic properties against Chlorella vulgaris 157 were also examined. 相似文献
24.
Yan-Ping Liu Li-Li Sun Xiang-Lin Zhang Hai-Yuan Niu Zheng-Hong Pan 《Natural product research》2020,34(16):2295-2300
Abstract A phytochemical investigation on the stems of Mappianthus iodoides led to the isolation of a new naturally occurring prenylated isoflavone, mappianthone A (1), together with seven known analogues (2?8). The structure of 1 was elucidated by extensive spectroscopic methods and the known compounds were identified by comparison with data reported in the literature. All isolated compounds were evaluated for their antiproliferative activities against five human cancer cell lines: HL-60, SMMC-7721, A-549, MCF-7 and SW480 in vitro. Compounds 1?8 showed significant antiproliferative effects against several human cancer cell lines with IC50 values ranging from 0.16 to 12.68?μM. 相似文献
25.
Talaat Ibrahim El‐Emary 《中国化学会会志》2006,53(2):391-401
New derivatives of pyrazolo[3,4‐b]pyrazine and related heterocycles were prepared starting from 6‐amino‐3‐methyl‐1‐phenyl‐1H‐pyrazolo[3,4‐b]pyrazine‐5‐carbonitrile ( 2 ) and using the key intermediates 4 , 5 , 6 , 14 , 15 and 16 . Some of the prepared compounds were evaluated for their antifungal and antibacterial activities. 相似文献
26.
Alessandro Pasini Franco Zunino 《Angewandte Chemie (International ed. in English)》1987,26(7):615-624
The clinical success of cisplatin (cis -diamminedichloroplatinum(II )) in antitumor chemotherapy has encouraged an all-out search for analogues with lower toxicity, improved therapeutic index and increased activity. Literally thousands of analogues, obtained by replacement of the ammine- and chloro-ligands by other amines and anionic ligands, respectively, have been systematically screened for activity in experimental tumor models. Some of these analogues have been selected for clinical evaluation, but only very few of them appear to be promising antitumor agents. More recently, cisplatin analogues have been designed and synthesized on the basis of, inter alia, the following considerations: 1) platinum complexes with carrier molecules as ligands should prove useful for achieving increasing drug concentration in tumor tissues; 2) platinum complexes with chemotherapeutic agents as ligands could afford polyfunctional drugs with synergistic action; 3) complexes containing more than one platinum atom might be more effective than complexes containing only one platinum atom; 4) platinum complexes could be used as sensitizers in radiation therapy. In this paper, we shall give a brief account of the “traditional” analogues, and then critically discuss what we believe could be the new trends in the design of cisplatin analogues. 相似文献
27.
Organoboron derivatives of biologically potent β‐enamino esters of the type [Where R = CH3(1a), C2H5 (1b), C3H7(1c) and C (CH3)3 (1d)] have been prepared by the reactions of β‐enamino esters and Phenyl boronic acid [PhB (OH)2] in 1:2 molar ratio in refluxing tetrahydrofuran (THF). All these derivatives have been characterized by physico‐chemical properties, elemental analyses and molecular weight measurements. The structures of these compounds have been proposed on the basis of IR, 1H, 13C, 11B NMR spectral data and GC‐mass spectrometry. Phenyl boronic acid, β‐enamino esters and their respective phenylboronates derivatives have been screened for the antibmicrobial activities against pathogenic bacteria (B. subtilis and E. coli) and fungi (A. niger and P. peniculosum) to access their growth inhibiting potential. In addition to this, antiandrogenic effect of Ligand, LaH2 and its boron derivative (1a) has also been tested in male albino rats. 相似文献
28.
A new procedure, which provides a closer approximation for the junction potentials than the Henderson equation, is tested to reduce new emf data for the chloride ion in CsCl solutions and previously measured data for individual ions in aqueous solutions of KCl, NaCl, and NaBr. The liquid junction potential is calculated from numerical integration of its basic equation without assuming constant mobility or using concentrations instead of activities. The mean ionic activity coefficients of the salts, obtained from the activity coefficients of the individual ions, show good agreement with values reported in the literature. The activity coefficients of the individual chloride ion at 25°C in aqueous solutions of CsCl up to 3 molal and in KCl solutions were measured using a chloride ion-selective electrode. It has been confirmed that the activity of the chloride ion is equal to the activity of the cation in CsCl solutions and, contrary to the prediction of hydration theory, it is higher than the activity of the cation in aqueous KCl solutions. The New Hydration Theory has been developed to overcome the shortcomings of the older hydration theory and has been used to smooth the experimental activity coefficients of the individual ions in aqueous solutions and to extrapolate them up to the saturated solution. 相似文献
29.
Yolanda Prieto Marcelo Muoz Vernica Arancibia Mauricio Valderrama Fernando J. Lahoz M. Luisa Martín 《Polyhedron》2007,26(18):5527-5532
The reaction of the dimer complex [{Ru(CO)3Cl2}2] with the ligands 4,6-dichloroquinoline-5,8-dione and 6-methoxybenzo[g]quinoline-5,10-dione in ethanol solution led to the neutral mononuclear complexes of general formula [Ru(CO)2Cl2(κ2-quinolinedione-N,O)]. The complexes were characterized by elemental analysis, IR and RMN spectroscopy, and the molecular structure of [Ru(CO)2Cl2(6-methoxybenzo[g]quinoline-5,10-dione)] was determined by single-crystal X-ray diffraction. The redox chemistry of ligands and complexes was investigated by cyclic voltammetry, and their potential antitumor activity was also evaluated. 相似文献
30.
Three new eremophilane‐type sesquiterpenes, (6β,8α)‐6‐(acetyloxy)‐8‐hydroxyeremophil‐7(11)‐en‐12,8‐olide ( 1 ), (6α,8α)‐6‐hydroxyeremophil‐7(11)‐en‐12,8‐olide ( 2 ), and (6α,8α)‐6‐(acetyloxy)eremophil‐7(11)‐en‐12,8‐olide ( 3 ) ((8α)‐eremophil‐7(11)‐en‐12,8‐olide = (4aR,5S,8aR,9aS)‐4a,5,6,7,8,8a,9,9a‐octahydro‐3,4a,5‐trimethylnaphtho[2,3‐b]furan‐2(4H)‐one), besides the recently elucidated eremoligularin ( 4 ) and bieremoligularolide ( 5 ), as well as a new highly oxygenated monoterpene, rel‐(1R,2R,3R,4S,5S)‐p‐menthane‐1,2,3,5‐tetrol ( 12 ), together with six known constituents, i.e., the sesquiterpenes 6 and 7 , the norsesquiterpenes 8 – 10 , and the monoterpene 13 , were isolated from the roots of Ligularia muliensis. In addition, an attempt to dimerize 1 to a bieremophilenolide (Scheme) resulted in the generation of the new derivative (6β,8β)‐6‐(acetyloxy)‐8‐chloroeremophil‐7(11)‐en‐12,8‐olide ( 11 ). The new structures were established by means of detailed spectroscopic analysis (IR, FAB‐, EI‐, or HR‐ESI‐MS as well as 1D‐ and 2D‐NMR experiments). Compounds 4 and 5 were evaluated for their antitumor effects in vitro (Table 3). 相似文献