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971.
El?bieta Hejchman Dorota Maciejewska Irena Wolska 《Monatshefte für Chemie / Chemical Monthly》2008,18(3):1337-1348
The microwave-assisted synthesis of four new 5-acetyl-4,7-dimethoxy-6-hydroxybenzofuran (khellinone) analogs is described.
The structures of the obtained derivatives in the solid state are evaluated on the basis of 13C CP/MAS NMR spectra and theoretical calculations at DFT level. A single crystal X-ray diffraction structure is presented
for 8-acetyl-7-hydroxy-4-methylcoumarin. 1,4-Bis(5-acetyl-4,7-dimethoxybenzofuran-6-yloxy)butane was evaluated for potential
anticancer activity in an in vitro screening panel of 60 human tumor cell lines. Selected leukemia, non-small cell lung cancer, CNS, melanoma, ovarian, and
breast cancer cell lines were sensitive to this compound. 相似文献
972.
Emad M. El-Telbani Mohamed F. El Shehry Galal A. M. Nawwar 《Monatshefte für Chemie / Chemical Monthly》2008,387(2):685-689
Synthesis of the title ring system is described using ethyl 4-(2,4-dichlorophenoxy)-3-oxobutanoate as starting material. The
latter was prepared through acylating Meldrum’s acid with the phenoxy acid chloride derivative. 相似文献
973.
5-(4-Methylpiperidino)methyl-2-thiouracil (1) has been obtained via the Mannich reaction between 2-thiouracil, paraformaldehyde, and a cyclic secondary amine such as 4-methylpiperidine (4-MP) in ethanol. New S,N(1)-di-o-(m- and p-)bromo-(nitro-) benzyl-substituted derivatives have been synthesized successfully in the reactions of 1 with the corresponding o-(m- and p-)bromobenzyl bromides or o-(m- and p-) nitrobenzyl chlorides in DMF solution in the presence of K2CO3. The opposite method of synthesis, that is, the reaction between 2-o-(m- and p-)bromobenzylthio-1-o-(m- and p-)bromobenzyluracils and 2-o-(m- and p-)nitrobenzylthio-1-o-(m- and p-) nitrobenzyluracils (8), with paraformaldehyde and 4-methylpiperidine in ethanol failed, indicating the important role of the enol form of 2-thiouracil for the Mannich reaction to be successful. 相似文献
974.
Fathy Abdel‐Kader Amer Metwally Hammouda Bakr Fathy Abdel‐Wahab Abdel‐Aziz Sayed El‐Ahl 《Journal of heterocyclic chemistry》2008,45(6):1549-1569
This review presents a survey of the synthetic methods and reactions of 3‐pyrrolidinones I (R = H, alkyl, acyl, ester; R1 = H, alkyl, cyano, ester, etc). 3‐Pyrrolidinones are synthetically versatiles substrate, as they can be used for synthesis of a large variety of heterocyclic compounds, such as indoles and 5‐deazapteroic acid analogues and as a raw material for drug synthesis. The high reactivity of an active methylene group next to the carbonyl of the pyrrolidine ring is useful for various syntheses. 相似文献
975.
Ramadan Ahmed Mekheimer Afaf Mohamed Abd El‐Hameid Kamal U. Sadek 《Journal of heterocyclic chemistry》2008,45(1):97-101
Reacting of 6‐azidopyridone derivatives 1 with o‐phenylenediamine ( 2a ) in chloroform at room temperature afforded the new azidopyridones 3 . However, its fusion with 2a,b at 100–110°C gave the interesting pyrido[2,3‐b][1,5]diazepines 4a,b . Alternatively, compound 4a could also be obtained by heating azidopyridones 3 at 100–110°C. When compound 1 was allowed to react with hydrazines 7a‐d at room temperature it gave the corresponding azido compounds 8a‐d . Fusion of 1 with phenylhydrazine ( 7d ) at 140–160°C afforded the new aminopyridones 10 . The 6‐azidopyridones 1 could also be converted to the corresponding 6‐alkylaminopyridones 15a‐d by reaction with an excess of alkylamines at room temperature. 相似文献
976.
Malek Taher Maghsoodlou Sayyed Mostafa Habibi Khorassani Lotfali Saghatforoush Farhad Maghfuri Ghasem Marandi Roya Kabiri 《Journal of heterocyclic chemistry》2008,45(1):289-293
High hindrance Hexa tert‐butoxy carbonyl dipyrrolophenanthroline and helical dihydropyrrolophen‐anthroline compounds were prepared from reactions between di tert‐butyl acetylenedicarboxylate and 1,10‐phenanthroline in polar solvents media. 相似文献
977.
Mohamed. R. Aouad Nadje T. Rezki El Sayed H. El Ahsry 《Journal of heterocyclic chemistry》2008,45(5):1321-1327
A solid support under microwave (MW) irradiation without solvent allowed the synthesis of the 2,3‐epoxy‐propyl‐thioimidazole 4 , regioselectively, and prohibited its cyclization to give the imidazo[2,1‐b]thiazine 3 from the reaction of 4,5‐diphenylimidazole‐2‐thione ( 1 ) with 1‐chloro‐2,3‐epoxy‐propane ( 2 ). The formation of the latter required basic conditions whereby it became the sole product; the change of the basic catalyst changed the ratio of the two products under both conventional and microwave (MW) conditions. A regioselective allylation of 1 with allyl bromide in presence of triethylamine gave the S‐allyl 8 , while in presence of potassium carbonate led to the S,N‐bis(allylated) derivative 9 . The intramolecular ring closure of 8 in presence of sulfuric acid afforded the imidazothiazole 16 . Protection of the sulfur in 1 and subsequent reaction with allyl bromide gave the N‐allylated derivative and with 2 gave N‐3‐chloro‐prop‐1‐yl derivative that shed light on the preferred route for the formation of 3 and 4 . The reactivity encountered during the alkylation of 1 with 2 has been theoretically investigated by using the AM1 method. 相似文献
978.
Subal Chandra Manna Georgina M. Rosair Golam Mostafa Nirmalendu Ray Chaudhuri 《Journal of solid state chemistry》2008,181(3):457-466
Three coordination complexes of Co(II)/Fe(II) with 4,4′-trimethylenedipyridine (bpp) and pseudohalides (SCN−, SeCN− and N3−) have been synthesized. The complexes have been characterized by X-ray single crystal structure determination. They are isomorphous having 2D layers in which two independent wavy nets display parallel interwoven structures. Pseudohalide binds metal centers through N terminal and occupies the trans axial positions of the octahedral metal coordination environment. Pseudohalide remains pendant on both sides of the polymeric layer and help the stacking through hydrogen bonding. The conformation of bpp in the interpenetrated nets is observed to be dependent on the choice of pseudohalide. 相似文献
979.
Saleh M. Al‐Mousawi Morsy A. El‐Apasery Najat Al‐Kandery Mohamed H. Elnagdi 《Journal of heterocyclic chemistry》2008,45(2):359-364
1‐[2‐Phenyl‐1‐diazenyl]‐1‐[2‐phenylhydrazono]acetone or 1‐[‐2‐(4‐methylphenyl)‐1‐diazenyl]‐1‐[‐2‐(4‐methylphenyl)hydrazono]‐butan‐2‐one were produced via coupling the (E) 2‐oxopropanal‐1‐phenyl‐hydrazone or (E) 2‐oxobutanal‐1‐(4‐methylphenyl)hydrazone with aromatic diazonium salts. These formazanes condensed readily with ethyl cyanoacetate to yield 5‐methyl‐3‐oxo‐2‐phenyl‐6‐phenylazo‐2,3‐dihydropyridazine‐4‐carbonitrile compound ( 9a ), 5‐ethyl‐3‐oxo‐2‐p‐tolyl‐6‐p‐tolylazo‐2,3‐dihydro‐pyridazine‐4‐carbonitrile and/or 5‐ethyl‐3‐oxo‐2,6‐di‐p‐tolyl‐2,3‐dihydropyridazine‐4‐carbonitrile that reacted with sulphur in presence of piperidine to yield the aminothienopyridazinones. The latter reacted with electron poor olefins and acetylenes to yield aminophthalazines. Compound ( 9a ) reacted also with benzylidenemalononitrile to yield the arylazophthalazinone. 相似文献
980.
M. El Masloumi V. Jubera J.P. Chaminade M. Mesnaoui B. Moine 《Journal of solid state chemistry》2008,181(11):3078-3085
Single crystals of NaY(PO3)4 and Ag0.07Na0.93Y(PO3)4 have been synthesized by flux method. These new compounds turned out to be isostructural to NaLn(PO3)4, with Ln=La, Nd, Gd and Er [monoclinic, P21/n, a=7.1615(2) Å, b=13.0077(1) Å, c=9.7032 (3) Å, β=90.55 (1)°, V=903.86(14) Å3 and Z=4]. The structure is based upon long polyphosphate chains running along the shortest unit-cell direction and made up of PO4 tetrahedra sharing two corners, linked to yttrium and sodium polyhedra. Infrared and Raman spectra at room temperature confirms this atomic arrangement. The luminescence of silver ions was reported in metaphosphate of composition Ag0.07Na0.93Y(PO3)4. One luminescent centre was detected and assigned to single Ag+ ions. 相似文献