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51.
Nasser Mohammed Hosny Mostafa A. Hussien Rana Motawa Arafa Belal Mohamed H. Abdel-Rhman 《应用有机金属化学》2020,34(11):e5922
2-(2-aminobenzoyl)-N-ethylhydrazine-1-carbothioamide (H3L) and its Cu (II), Co (II), Ni (II) and Zn (II) complexes have been synthesized. The structures of the isolated compounds were suggested based on elemental analyses, spectral analyses (FTIR, 1H and 13CNMR, MS, ESR and UV–Visible) and magnetic moments measurements. The free ligand exists in the keto-thione form, while in the metal complexes; it exists in the enol form and coordinates as mononegative bidentate via deprotonated enolic oxygen and N2H nitrogen. Both Co (II) and Ni (II) complexes have an octahedral, while Cu (II) complex has a square planar geometry. The compounds have direct electronic transitions with optical band gap (Eg) values in the range 3.14–3.40 eV. The ligand and its complexes were optimized using DFT/B3LYP methodology. The ligand optimization results supported the involvement of the carbonyl oxygen, thione sulfur and N2H hydrogen atoms in hydrogen bonding formation. Furthermore, the obtained structures of the ligand and its complexes were subjected to molecular docking study to predict interactions cause their cytotoxicity. Finally, the in vitro cytotoxicity activities of the ligand and its complexes were investigated against Hela and WISH cell lines where the Zn (II) complex exhibited higher activity than the other compounds against the two cell lines in accordance with molecular docking suggestion. 相似文献
52.
The formation equilibria for the binary complexes of Cu(II), Ni(II), Co(II), Zn(II), Mn(II), Hg(II), Cd(II), Ca(II), and Mg(II) with cefadroxil (Cef) and for the ternary complexes Cu(Cef)(L), where L refers to amino acid or DNA, were investigated. The protonation constants of cefadroxil and formation constants of the formed complexes were determined at 25 degrees C and mu = 0.1 M NaNo(3). Cooper(II) and cobalt(II) complexes of cefadroxil were isolated in solid state and characterized by elemental analysis, infrared and electronic spectral, conductivity and magnetic measurement. 相似文献
53.
An algorithm is described to derive the transfer function of two variable networks or systems from the state equations. The algorithm is suitable for computer-aided procedures and gives recurrence relations from which the coefficients of the transfer function can be calculated. An alternative to this algorithm is to solve the state equations directly which requires a matrix inversion step at each frequency. By using the algorithm the coefficients of the transfer function are calculated only once and this offers substantial saving in computer time. 相似文献
54.
Hatem A. Elbatal Zeinab S. Mandouh Hamdia A. Zayed Samir Y. Marzouk Gihan M. Elkomy Ahmed Hosny 《Journal of Non》2012,358(15):1806-1813
This research aims to investigate and compare the structural and the morphological properties of both lithium disilicate glasses doped with copper oxide and their glass–ceramic derivatives. Density measurements were measured for all samples by Archimedes method at room temperature. Differential scanning calorimetric analysis was used to determine the glass transition temperature (Tg) and crystallization temperature (Tc) for all glasses. The glass transition temperature was observed to decrease with increasing CuO concentration indicating the formation of non-bridging oxygen bonds in the glass network. X-ray analysis patterns reveal the appearance of crystalline lithium metasilicate phase as the main phase within the glass–ceramic derivatives, and their crystallite sizes were observed to decrease as the CuO increased. Experimental infrared absorption data indicate the existence of characteristic vibrational bands due to structural building SiO4 units in resemblance to the same vibrations observed from traditional crystalline silicates. Scanning electron microscopic investigations show the vitreous nature for lithium disilicate glasses and the distinct crystalline morphological features for the corresponding glass–ceramic derivatives. 相似文献
55.
The interaction between imidazole (L1), 2-isopropylimidazole (L2), 2-amino-benzimidazole (L3) and 2-(2-pyridyl)benzimidazole (L4) (L in general), and dimethyltin chloride in water have been investigated at 25 degrees C and ionic strength of 0.1 M sodium nitrate using the potentiometric technique. The results showed the formation of 1:1 and 1:2 (organotin:ligand) complexes and the corresponding stability constants were determined. The effect of the pKa values of the respective ligands on the stability constants of its complex species was elucidated. The concentration distribution of the complexes in solution was evaluated. Also, their solid complexes of the general formula in diethylether-dichloromethane, give 1:2 (organotin:Ligand) [(L)2 (CH3)2 SnCl2.zH2O][L = L1, z = 0 and L = L2, z = 1] and 1:1 [L (CH3)2 SnCl2.zH2O][L = L3, z = 0 and L = L4, z = 2]. The separated solid products were characterized by elemental analyses (C, H, N, Cl), IR, mass spectra, thermogravimetric analysis (TGA) and magnetic susceptibility. The participation of the ligand functional groups in bonding to the organotin (IV) was discussed. Conductivity and 1H-NMR spectra were used to confirm the behaviour of these complexes in solution. 相似文献
56.
WM.B. Peatman Gerald B. Kasting David J. Wilson 《Journal of Electron Spectroscopy and Related Phenomena》1975,7(3):233-246
Autoionization electrons in threshold photoionization spectra are known to occur. The effect of such electrons on the interpretation of threshold electron spectra is discussed and a new method is described which enables one to discriminate between zero kinetic energy electrons and energetic electrons in photoionization experiments with little ambiguity. The method largely overcomes the main problem present in some previously described threshold electron studies; namely, the line-of-sight transmission of energetic electrons which gives rise to non-threshold electron peaks. A rejection ratio of 25 is readily obtained for 0.038 eV electrons compared with threshold (zero kinetic energy) electrons and the (small) transition probability for energetic electrons falls off more rapidly than for analysers previously described. Design parameters based on electron trajectory calculations are given for the analyser used, and photoionization results on argon are presented. 相似文献
57.
Structural Chemistry - The premise leading to this investigation was based on the following: if a class of compounds has desirable crystallization behavior(s), can one translate that information to... 相似文献
58.
Hala M. Alkhalidi Amerh Aiad Alahmadi Waleed Y. Rizg Esam Bashir Yahya Abdul Khalil H.P.S. Rayan Y. Mushtaq Moutaz Y. Badr Awaji Y. Safhi Khaled M. Hosny 《Macromolecular rapid communications》2024,45(9):2300687
Cancer stands as a leading cause of global mortality, with chemotherapy being a pivotal treatment approach, either alone or in conjunction with other therapies. The primary goal of these therapies is to inhibit the growth of cancer cells specifically, while minimizing harm to healthy dividing cells. Conventional treatments, often causing patient discomfort due to side effects, have led researchers to explore innovative, targeted cancer cell therapies. Thus, biopolymer-based aerogels emerge as innovative platforms, showcasing unique properties that respond intelligently to diverse stimuli. This responsiveness enables precise control over the release of anticancer drugs, enhancing therapeutic outcomes. The significance of these aerogels lies in their ability to offer targeted drug delivery with increased efficacy, biocompatibility, and a high drug payload. In this comprehensive review, the author discuss the role of biopolymer-based aerogels as an emerging functionalized platforms in anticancer drug delivery. The review addresses the unique properties of biopolymer-based aerogels showing their smart behavior in responding to different stimuli including temperature, pH, magnetic and redox potential to control anticancer drug release. Finally, the review discusses the application of different biopolymer-based aerogel in delivering different anticancer drugs and also discusses the potential of these platforms in gene delivery applications. 相似文献
59.
Nasser Mohammed Hosny 《Transition Metal Chemistry》2007,32(1):117-124
Mixed ligand complexes [M(2-AP)(Ala)Cl
x
· mH2O]nH2O, where (M = CoII, NiII, CrIII and FeIII, 2-AP = 2-acetylpyridine, Ala = alanine, x = 2–3, m = 0–1 and n = 3–5] are synthesized and characterized by elemental analysis, FTIR, UV/Vis., MS, TG, measurements and semi-empirical calculations
ZINDO/1 and PM3. The results suggest an octahedral geometry for all isolated complexes. FTIR spectra show that alanine coordinates
to the metal ions as a neutral unidentate through the amino nitrogen where 2-acetylpyridine coordinates to the metal ion in
a bidentate manner through carbonyl oxygen and pyridyl nitrogen. Semi-empirical calculations have been used to study the molecular
geometry and the harmonic vibrational spectra with the purpose to assist the experimental assignment of the complexes. The
Fe complex showed significant activity as a catalase-like model. 相似文献
60.
Altaf H. Basta Wafaa M. Hosny Houssni El-Saied Afkar K. Abdel Hadi 《Cellulose (London, England)》1996,3(1):1-10
Reactions of hydroxyethyl cellulose (HEC) with Cr
III, NiII, CoII, or CuII chlorides in aqueous medium yielded complexes with formulae [M(HEC)Cl
m
.n
H
2O], wherem
=1 or 2 and
n=2 or 3. HEC acted as a uninegatively charged bidentate ligand in the case of CrIII and NiII, and as a neutral ligand in the case of CoII and CuII complexes. The spectra showed that the binding sites in CrIII and NiII complexes were the ether oxygen between two ethoxyl groups and the oxygen of the hydroxyl group; while in the CoII and CuII complexes the binding sites were the oxygen of ethoxyl groups and the primary alcoholic O atom of glucopyranose rings. These complexes would most likely exhibit octahedral geometry with CrIII, NiII, and CoII, but square planar configuration in the case of the CuII complex. The ligand parameters of the CrIII, NiII, and CoII metal chelates were calculated in different solvents and at different temperatures. The thermal stability of the above complexes was investigated and the overall thermodynamics functions G0, H0, and S0, associated with complex formation, were estimated. 相似文献