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321.
Tushar S. Basu Baul Khrawborlang Nongsiej Augustine Lamin Ka‐Ot Santa Ram Joshi Irn Rojas Len Herbert Hpfl 《应用有机金属化学》2019,33(7)
A series of six new Zn (II) compounds, viz., [Zn(HLASA)2(Py)2] ( 1 ), [Zn(HLMASA)2(Py)2] ( 2 ), [Zn(HLMASA)2(4‐MePy)2] ( 3 ), [Zn(HLCASA)2(4‐MePy)2] ( 4 ), [Zn(HLBASA)2(Py)2] ( 5 ), [Zn(HLBASA)2(4‐MePy)2] ( 6 ) and representative Cu (II) and Cd (II) complexes, viz., [Cu(HLASA)2(Py)2(H2O)] ( 7 ) and [Cd(HLBASA)2(Py)3] ( 8 ) [(HLXASA)? = para‐substituted 5‐[(E)‐2‐(aryl)‐1‐diazenyl]‐2‐hydroxybenzoate with X = H (ASA), Me (MASA), Cl (CASA) or Br (BASA); Py = pyridine; 4‐MePy = 4‐methylpyridine] have been synthesized and characterized by spectroscopic techniques and single‐crystal X‐ray diffraction analysis. The structural characterization of the compounds revealed distorted tetrahedral ( 1 – 6 ), square‐pyramidal ( 7 ) and pentagonal‐bipyramidal ( 8 ) coordination geometries around the metal atom, in which the aryl‐substituted diazosalicylate ligands are coordinated only through the oxygen atoms of carboxylate groups, either in an anisobidentate or isobidentate mode; meanwhile, the 2‐hydroxy groups of the monoanionic ligand (HLXASA)? are involved only in intramolecular O‐H···O hydrogen bonds with the carboxylate function. In the crystal structures of 1 – 8 , the complex molecules are assembled by π‐stacking interactions giving mostly infinite 1D strands. The intermolecular binding in the solid state structures is accomplished by diverse additional non‐covalent contacts including C‐H···O, C‐H···N, C‐H···π, C‐H···Br, O···Br, Br···π and van der Waals contacts. Although the primary and secondary ligands in the Zn (II) complex series 1 – 6 carry different substituents at the periphery (X = H, Me, Cl, Br for (HLXASA)? and R = H, Me for 4‐Py‐R), five of the crystal structures were isostructural. Additionally, the antimicrobial activity of the pro‐ligands H2LXASA and their Zn (II), Cu (II) and Cd (II) compounds were studied in a comparative manner, showing high sensitivity (IZD ≥ 20) against Bacillus subtilis. 相似文献
322.
Das Tushar Kanti Ganguly Sayan Bhawal Poushali Mondal Subhadip Das Narayan Ch 《Research on Chemical Intermediates》2018,44(2):1189-1208
Research on Chemical Intermediates - Silver nanoparticles (AgNPs) were gradually grown on a hydroxyapatite surface via a green self-reducing approach. Hydroxyapatite (HAP) was functionalized by... 相似文献
323.
Priyanka Maiti Priyanka Sharma Mahesha Nand Indra D. Bhatt Muthannan Andavar Ramakrishnan Shalini Mathpal Tushar Joshi Ragini Pant Shafi Mahmud Jesus Simal-Gandara Sultan Alshehri Mohammed M. Ghoneim Maha Alruwaily Ahmed Abdullah Al Awadh Mohammed Merae Alshahrani Subhash Chandra 《Molecules (Basel, Switzerland)》2022,27(5)
Among the various types of cancer, lung cancer is the second most-diagnosed cancer worldwide. The kinesin spindle protein, Eg5, is a vital protein behind bipolar mitotic spindle establishment and maintenance during mitosis. Eg5 has been reported to contribute to cancer cell migration and angiogenesis impairment and has no role in resting, non-dividing cells. Thus, it could be considered as a vital target against several cancers, such as renal cancer, lung cancer, urothelial carcinoma, prostate cancer, squamous cell carcinoma, etc. In recent years, fungal secondary metabolites from the Indian Himalayan Region (IHR) have been identified as an important lead source in the drug development pipeline. Therefore, the present study aims to identify potential mycotic secondary metabolites against the Eg5 protein by applying integrated machine learning, chemoinformatics based in silico-screening methods and molecular dynamic simulation targeting lung cancer. Initially, a library of 1830 mycotic secondary metabolites was screened by a predictive machine-learning model developed based on the random forest algorithm with high sensitivity (1) and an ROC area of 0.99. Further, 319 out of 1830 compounds screened with active potential by the model were evaluated for their drug-likeness properties by applying four filters simultaneously, viz., Lipinski’s rule, CMC-50 like rule, Veber rule, and Ghose filter. A total of 13 compounds passed from all the above filters were considered for molecular docking, functional group analysis, and cell line cytotoxicity prediction. Finally, four hit mycotic secondary metabolites found in fungi from the IHR were screened viz., (−)-Cochlactone-A, Phelligridin C, Sterenin E, and Cyathusal A. All compounds have efficient binding potential with Eg5, containing functional groups like aromatic rings, rings, carboxylic acid esters, and carbonyl and with cell line cytotoxicity against lung cancer cell lines, namely, MCF-7, NCI-H226, NCI-H522, A549, and NCI H187. Further, the molecular dynamics simulation study confirms the docked complex rigidity and stability by exploring root mean square deviations, root mean square fluctuations, and radius of gyration analysis from 100 ns simulation trajectories. The screened compounds could be used further to develop effective drugs against lung and other types of cancer. 相似文献
324.
Copolymer compositions and reactivity ratios for the radical copolymerization of styrene with acrylonitrile have been determined by x-ray photoelectron spectroscopy (XPS). The results obtained by this technique were confirmed by elemental as well as 1H-NMR (nuclear magnetic resonance) analysis. The monomer sequence distributions have also been calculated utilizing the monomer reactivity ratio values obtained by three different techniques viz., XPS, 1H-NMR, and elemental analysis. The agreement between the monomer sequence distributions in the copolymer chain by these methods is very satisfactory. © 1997 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 35: 2049–2056, 1997 相似文献
325.
326.
Amit Basak Subhendu Sekhar Bag Kakali Rani Rudra Jharna Barman Sumana Dutta 《ChemInform》2002,33(48):115-115
327.
328.
The total synthesis of panaginsene has been accomplished in 11 linear steps starting from methyl 3,3-dimethyl-5-oxocyclopent-1-ene-1-carboxylate. The key steps are a Sharpless asymmetric epoxidation and Ti(III)-mediated reductive epoxide opening-radical cyclization to construct the chiral quaternary carbon stereocenter followed by a very challenging HWE olefination reaction on an 1,3-keto aldehyde and a late stage McMurry olefination using low valent titanium to construct the highly constrained angular tetrasubstituted olefin in a five-membered ring. 相似文献
329.
A delayed prey–predator model with Crowley–Martin‐type functional response including prey refuge 下载免费PDF全文
Atasi Patra Maiti B. Dubey Jai Tushar 《Mathematical Methods in the Applied Sciences》2017,40(16):5792-5809
In this paper, we have studied a prey–predator model living in a habitat that divided into two regions: an unreserved region and a reserved (refuge) region. The migration between these two regions is allowed. The interaction between unreserved prey and predator is Crowley–Martin‐type functional response. The local and global stability of the system is discussed. Further, the system is extended to incorporate the effect of time delay. Then the dynamical behavior of the system is analyzed, taking delay as a bifurcation parameter. The direction of Hopf bifurcation and the stability of the bifurcated periodic solution are determined with the help of normal form theory and centre manifold theorem. We have also discussed the influence of prey refuge on densities of prey and predator species. The analytical results are supplemented with numerical simulations. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
330.
Yashoda Krishna Sunkari Chandan Pal Thota Jagadeshwar Reddy Tushar Kanti Chakraborty 《Tetrahedron》2014
A convenient protocol is developed for the synthesis of 3′-[N-(fluorenylmethoxycarbonyl)-amino]-5′-carboxymethyl derivatives of all four natural ribonucleosides from cheap chiral pool compound glucose. Synthesis of fully amide-linked RNA analogues of small oligonucleotides containing, for the first time, all four nucleoside amino acids using standard solid phase Fmoc-chemistry is described. 相似文献