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排序方式: 共有106条查询结果,搜索用时 15 毫秒
91.
Huda R. M. Rashdan Marwa S. El-Gendey Maher A. El-Hashash Abdel Mohsen M. Soliman 《Green Chemistry Letters and Reviews》2018,11(3):264-274
This work focuses the light on some remarkable achievements in clean and efficient green experimental synthesis, characterization and evaluation of the pharmaceutical and biochemical importance of new series of pyrazolo[1,2-b]phthalazinediones which synthesized through one-pot three-component condensation reaction of the appropriate of 1,2,3-triazolyl-pyrazole-carbaldehydes with active methylene compounds (as malononitriles or ethyl cyanoacetate) and 6-nitrophthalhydrazide using the grinding method in the presence of sodium hydroxide under solvent-free condition at room temperature, in very excellent yields. All the newly synthesized compounds were characterized by physical and chemical tools (FT-IR, 1H NMR and mass spectrometry). In addition, all the new synthesized derivatives were screened for their anticancer activity against hepatic cancer cell lines to evaluate their pharmaceutical importance. 相似文献
92.
Mohd Syafiq Zulfakar Huda Abdullah Wan Nasarudin Wan Jalal Zalita Zainuddin Sarada Idris 《Journal of Sol-Gel Science and Technology》2014,71(3):413-420
Sol–gel method was used to synthesize zinc aluminate (ZnAl2O4) dispersed into silica matrix with different compositions of x. Morphological structure of (1?x)ZnAl2O4–xSiO2 samples were investigated by field emission scanning electron microscope (FESEM) and X-ray diffractometer (XRD). The FESEM images showed spherical structures and agglomerated particles occurred inside the samples. XRD analysis indicated the cubic phase formation of the samples. The crystallite size, D was calculated and it was found that the crystallite size are slightly increased from 8 to 17 nm. FTIR spectra analysis shows that the water presence in the samples and also the presence of nitrate group. The dielectric properties have been measured, ε r value was found to be around 13.0. The S11 parameter analysis shows the samples was resonated at 2.40 GHz and gives different values of bandwidth for microstrip patch antenna application. 相似文献
93.
Green One‐Pot Solvent‐Free Synthesis of Pyrazolo[1,5‐a]pyrimidines,Azolo[3,4‐d]pyridiazines,and Thieno[2,3‐b]pyridines Containing Triazole Moiety 下载免费PDF全文
Abdou O. Abdelhamid Tamer T. El‐Idreesy Nadia A. Abdelriheem Huda R. M. Dawoud 《Journal of heterocyclic chemistry》2016,53(3):710-718
Synthesis of pyrazolo[1,5‐a]pyrimidines, [1,2,4]triazolo[1,5‐a]pyrimidine, 8,10‐dimethyl‐2‐(5‐methyl‐1‐phenyl‐4,5‐dihydro‐1H‐1,2,3‐triazol‐4‐yl)pyrido[2′,3′:3,4]‐pyrazolo[1,5‐a]pyrimidine, benzo[4,5]imidazo[1,2‐a]pyrimidine via heterocyclic amines, and sodium 3‐hydroxy‐1‐(5‐methyl‐1‐phenyl‐1H‐1,2,3‐triazole‐4‐yl)prop‐2‐en‐1‐one were carried out. Also, synthesis of isoxazoles, and pyrazoles from sodium 3‐hydroxy‐1‐(5‐methyl‐1‐phenyl‐1H‐1,2,3‐triazole‐4‐yl)prop‐2‐en‐1‐one and hydroxymoyl chlorides and hydrazonoyl halides, respectively, were made. Analogously, (1,2,3‐triazol‐4‐yl)thieno[2,3‐b]pyridine derivatives were obtained from sodium 3‐hydroxy‐1‐(5‐methyl‐1‐phenyl‐1H‐1,2,3‐ triazole‐4‐yl)prop‐2‐en‐1‐one and cyanothioacetamide followed by its reacting with active methylene compounds. In addition to full characterization of all synthesized compounds, they were tested to evaluate their antimicrobial activities, and some compounds showed competitive activities to those of tetracycline, the typical antibacterial drug, and clotrimazole, the typical antifungal drug. 相似文献
94.
95.
Huda R. M. Rashdan Aboubakr H. Abdelmonsef Mortaga M. Abou-Krisha Tarek A. Yousef 《Molecules (Basel, Switzerland)》2021,26(23)
2-azido-1H-benzo[d]imidazole derivatives 1a,b were reacted with a β-ketoester such as acetylacetone in the presence of sodium ethoxide to obtain the desired molecules 2a,b. The latter acted as a key molecule for the synthesis of new carbazone derivatives 4a,b that were submitted to react with 2-oxo-N-phenyl-2-(phenylamino)acetohydrazonoyl chloride to obtain the target thiadiazole derivatives 6a,b. The structures of the newly synthesized compounds were inferred from correct spectral and microanalytical data. Moreover, the newly prepared compounds were subjected to molecular docking studies with DNA gyrase B and exhibited binding energy that extended from −9.8 to −6.4 kcal/mol, which confirmed their excellent potency. The compounds 6a,b were found to be with the minimum binding energy (−9.7 and −9.8 kcal/mol) as compared to the standard drug ciprofloxacin (−7.4 kcal/mol) against the target enzyme DNA gyrase B. In addition, the newly synthesized compounds were also examined and screened for their in vitro antimicrobial activity against pathogenic microorganisms Staphylococcus aureus, E. coli, Pseudomonas aeruginosa, Aspergillus niger, and Candida albicans. Among the newly synthesized molecules, significant antimicrobial activity against all the tested microorganisms was obtained for the compounds 6a,b. The in silico and in vitro findings showed that compounds 6a,b were the most active against bacterial strains, and could serve as potential antimicrobial agents. 相似文献
96.
Huda Farid Ernst Haslinger Olaf Kunert Christian Wegner Matthias Hamburger 《Helvetica chimica acta》2002,85(4):1019-1026
Five new steroidal glycosides were isolated from the roots of Balanites aegyptiaca, a widely used African medicinal plant. On the basis of spectroscopic and chemical evidence, their structures were determined as (3β,12α,14β,16β)‐12‐hydroxycholest‐5‐ene‐3,16‐diyl bis(β‐D ‐glucopyranoside) ( 1 ), (3β,20S,22R,25R)‐ and (3β,20S,22R,25S)‐26‐(β‐D ‐glucopyranosyloxy)‐22‐methoxyfurost‐5‐en‐3‐yl β‐D ‐xylopyranosyl‐(1→3)‐β‐D ‐glucopyranosyl‐(1→4)[α‐L ‐rhamnopyranosyl‐(1→2)]‐β‐D ‐glucopyranoside ( 2 and 3 , resp.), and (3β,20S,22R,25R)‐ and (3β,20S,22R,25S)‐spirost‐5‐en‐3‐yl β‐D ‐xylopyranosyl‐(1→3)‐β‐D ‐glucopyranosyl‐(1→4)[α‐L ‐rhamnopyranosyl‐(1→2)]‐β‐D ‐glucopyranoside ( 4 and 5 , resp.) 相似文献
97.
S. Huda 《Annals of the Institute of Statistical Mathematics》1982,34(1):365-371
Summary Some new third-order rotatable designs in three dimensions are derived from some of the available third-order rotatable designs
in two dimensions. When these designs are used the results of the experiments performed according to the two-dimentional designs
need not be discarded. Some of these designs may be performed sequentially in all three factors, starting with a one-dimensional
design. Further, these third-order rotatable designs require a smaller number of points than most of the available three-dimensional
third-order rotatable designs. 相似文献
98.
Huda Izzat OmarYuka Odo Yasuhiro ShigemitsuTetsuro Shimo Kenichi Somekawa 《Tetrahedron》2003,59(41):8099-8105
The experimental results of the triplet [2+2] photocycloaddition reactions of substituted 2-cyclohexenone 1 with cycloalkenylesters 2, 3, 4 have showed remarkable change in the regioselectivity of the products. The ht/hh product ratio increases with increment of the cycle-size. The FMO investigations in addition to the transition state analysis were used to rationalize such regioselectivity. The FMO method with their orbital coefficients and energies could not explain the reaction selectivity since these values of 2-4 showed tendency to form the hh adduct mainly. PM3, PM5, CIS/6-31G, and B3LYP/6-31G methods were used to locate the hh and ht transition states of the three reactions. As the potential energy barriers (TS1) on the first TS surface for the major products were lower than that for the minor products in most of the cases, the real ratio can be explained in terms of TS analysis. The recently improved PM5 and the B3LYP methods were more successful in this debate as partitioning the activation energy at the potential energy barriers into reactant deformation and the interaction (or repulsion) energies is easy and effective. The changes in the ht/hh ratio with the enlargement of the alkene ring size may be due to the increment of the repulsion energy and large changes in the deformation energy of the reactants. In the transition state structures the stabilities of the major products are thought to be due to the existence of some repulsion between the enone carbonyl and esters in the alkenylesters, and some hydrogen bonding between the reactants. The FMO and second transition state (TS2) energy on the biradical intermediates are also thought to play some role in controlling the product selectivity by lowering the closure energy of the biradicals according to the possibility of their overlapping. 相似文献
99.
M.K. Huda 《Journal of luminescence》2010,130(11):2242-2246
Photoluminescence properties of a new series of soluble 1,3-bis(phenyl-1,3,4-oxadiazole)s bearing polar groups in the main chain like -NO2, −OH, −CH3 and -Cl have been studied. The photoluminescence spectra show significant shift in the emission wavelengths in solid as well as in solution depending on the groups attached in the main chain, both redshift (electron withdrawing group) and blueshift (electron donating group) and change in the intensity of the emissive spectra as compared with those of the simple polyoxadiazoles at ∼300 nm. Quantum yield measurement with reference to anthracene indicates increase in the quantum efficiency many folds with decrease in concentration. The polymers are found to be thermally stable up to 350-400 °C and their glass transition temperature ranges between 100 and 150 °C. 相似文献
100.
Pratibha Pandey Fahad Khan Faisal Abdulrahman Alzahrani Huda A. Qari Mohammad Oves 《Molecules (Basel, Switzerland)》2021,26(18)
Rutin has been well recognized for possessing numerous pharmacological and biological activities in several human cancer cells. This research has addressed the inhibitory potential of rutin against the Jab1 oncogene in SiHa cancer cells, which is known to inactivate various tumor suppressor proteins including p53 and p27. Further, the inhibitory efficacy of rutin via Jab1 expression modulation in cervical cancer has not been yet elucidated. Hence, we hypothesized that rutin could exhibit strong inhibitory efficacy against Jab1 and, thereby, induce significant growth arrest in SiHa cancer cells in a dose-dependent manner. In our study, the cytotoxic efficacy of rutin on the proliferation of a cervical cancer cell line (SiHa) was exhibited using MTT and LDH assays. The correlation between rutin and Jab1 mRNA expression was assessed by RT-PCR analysis and the associated events (a mechanism) with this downregulation were then explored via performing ROS assay, DAPI analysis, and expression analysis of apoptosis-associated signaling molecules such as Bax, Bcl-2, and Caspase-3 and -9 using qRT-PCR analysis. Results exhibit that rutin produces anticancer effects via inducing modulation in the expression of oncogenes as well as tumor suppressor genes. Further apoptosis induction, caspase activation, and ROS generation in rutin-treated SiHa cancer cells explain the cascade of events associated with Jab1 downregulation in SiHa cancer cells. Additionally, apoptosis induction was further confirmed by the FITC-Annexin V/PI double staining method. Altogether, our research supports the feasibility of developing rutin as one of the potent drug candidates in cervical cancer management via targeting one such crucial oncogene associated with cervical cancer progression. 相似文献