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241.
Cemil İbiş Hatice Yıldırım 《Phosphorus, sulfur, and silicon and the related elements》2013,188(2):369-378
N,S-Substituted nitrobutadienes 3a–g were synthesized from the reaction of the thiosubstituted derivatives 1a–g with thiomorpholine 2. The N,S-substituted nitrobutadienes 5a–g were obtained from the reaction of the thiosubstituted butadienes 1a–g with N-diphenylmethyl piperazine 4. The structure of butadiene 3c was elucidated by single crystal X-ray diffraction. 相似文献
242.
Metin Zora Ay?e Nur Pinar Orhan Büyükgüngör Günseli Turgut 《Journal of organometallic chemistry》2008,693(1):145-154
Synthesis of ferrocenyl-substituted pyrazoles via the reaction between 3-ferrocenylpropynal and hydrazinium salts is described. Depending upon the substitution pattern of hydrazine derivative, the reaction affords 1-alkyl/aryl-5-ferrocenylpyrazoles and/or 1-alkyl/aryl-3-ferrocenylpyrazoles. Structures of 5-ferrocenyl-1-phenyl-1H-pyrazole, 1-benzyl-5-ferrocenyl-1H-pyrazole and 2-(3-ferrocenylpyrazol-1-yl)ethanol were identified by X-ray crystallography. 相似文献
243.
244.
In this paper, approximate-exact solutions of a class of Lane–Emden type singular IVPs problems, by the variational iteration method, are presented. The variational iteration method yields solutions in the forms of convergent series with easily calculable terms. The scheme is shown to be highly accurate, and in some cases, yields exact solutions in few iterations. 相似文献
245.
Cem Öztürk Hatice Mutlu Michael A.R. Meier Selim H. Küsefo?lu 《European Polymer Journal》2011,47(7):1467-1476
In this work new radically polymerizable triglyceride based monomers were synthesized by the reaction of epoxidized methyl oleate (EMO) and epoxidized soybean oil (ESO) with 4-vinyl benzene sulfonic acid (4VBSA). The products are 1-(4-vinylbenzene sulfonyl)oxy-2-alkonols of epoxidized soybean oil (SESO) and 1-(4-vinylbenzene sulfonyl)oxy-2-alkonols of epoxidized methyl oleate (SEMO). These adducts were characterized by 1H NMR, 13C NMR, IR and CHNS elemental analysis. SESO was found to contain, on the average, 2.47 4VBSA units per triglyceride. SESO was free radically polymerized and co-polymerized with styrene and the mechanical and thermal properties of the resulting thermosets were determined by DMA, DSC and TGA. SEMO was used as a model compound to determine the efficiency of metathesis catalysts for these fatty acid derivatives. The second generation Hoveyda–Grubbs catalyst was found to give best yields. ADMET polymerization of SESO with this catalyst with and without solvent gave ∼80% yield of a thermoset polymer. Polymers obtained by free radical route swelled in water at room temperature, and hydrolyzed in water at 60 °C. 相似文献
246.
Gören AC Akçicek E Dirmenci T Kilic T Mozioğlu E Yilmaz H 《Natural product research》2012,26(1):84-90
The fatty acid composition of the seed oil of 23 Stachys taxa was analysed by GC/MS. The main compounds were found to be linoleic (27.1-64.3%), oleic (20.25-48.1%), palmitic (4.3-9.1%), stearic (trace to 5.2%) and 6-octadecynoic (2.2-34.1%) acids. The latter compound could be used as a chemotaxonomic marker of the genus Stachys. A cluster analysis was performed for comparison and characterisation of the seed oil from Stachys species. 相似文献
247.
用胺甲基树脂与5-氟-2-羟基苯甲醛,5-氟-3-氯-2-羟基苯甲醛,5-氟-3-甲基-2-羟基苯甲醛反应合成了3种新颖的高分子担载席夫碱和它们Cr(Ⅲ)配合物,并用元素分析、磁化率、IR、1HNMR、UV-Vis、TG/DTA对其进行了表征。就一些革兰氏阳性菌(芽孢杆菌属腊状芽孢杆菌(Bacillus cereus sp),单核细胞增生李斯特菌4b(Listeria monocytogenes 4b),藤黄微球菌(Micrococcus luteus),金黄色葡萄球菌(Staphylococcus aureus)表皮葡萄球菌(Staphylococcus epidermis))和革兰氏阴性菌(布鲁氏菌(Brucella abortus),大肠杆菌(Escherichia coli),恶臭假单胞菌SP(Pseudomonas putidasp.),痢疾志贺氏菌10(Shigella dysenteria type 10),伤寒杆菌H(Salmonella typhi H)和酵母菌(念珠菌)(yeast(Candida albicans))用井扩散法对高分子担载席夫碱和它们Cr(Ⅲ)配合物的生物学活性进行了筛选。 相似文献
248.
Hydrogen transfer reduction processes are attracting increasing interest from synthetic chemists in view of their operational simplicity. Reaction of [Ph2PNHCH2‐C4H3S] with [Ru(η6‐benzene)(µ‐Cl)Cl]2, [Rh(µ‐Cl)(cod)]2 and [Ir(η5‐C5Me5)(µ‐Cl)Cl]2 gave a range of new monodendate complexes [Ru(Ph2PNHCH2‐C4H3S)(η6‐benzene)Cl2], 1, [Rh(Ph2PNHCH2‐C4H3S)(cod)Cl], 2, and [Ir(Ph2PNHCH2‐C4H3S)(η5‐C5Me5)Cl2], 3, respectively. All new complexes were fully characterized by analytical and spectroscopic methods. 1H? 31P NMR, 1H? 13C HETCOR or 1H? 1H COSY correlation experiments were used to confirm the spectral assignments. 1–3 are suitable catalyst precursors for the transfer hydrogenation of acetophenone derivatives. Notably [Ru(Ph2PNHCH2‐C4H3S)(η6‐benzene)Cl2], 1, acts as an excellent catalyst, giving the corresponding alcohols in 98–99% yields in 30 min at 82 °C (TOF ≤200 h?1) for the transfer hydrogenation reaction in comparison to analogous rhodium or iridium complexes. This transfer hydrogenation is characterized by low reversibility under these conditions. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
249.
Mustafa Odabaşoğlu Şükriye Çakmak Günseli Turgut Hasan İçbudak 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):549-558
Some new substituted cyclotriphosphazenes were prepared by reaction of hexachlorocyclotriphosphazene and phenylazophenylazophenol compounds such as p -[ p -phenylazo-phenylazo]phenol, p -[ p -( o -chlorophenylazo)phenylazo]phenol, p -[ p -( p -chlorophenylazo)phenylazo]phenol, p -[ p -( p -methylphenylazo)phenylazo]phenol, and tetrazobenzene- g -naphtol. They are characterized by UV-Vis, FT IR, elemental analysis, and TG, DTG, and DTA. 相似文献
250.
Two natural diarylheptanoids, 2‐benzyl‐5‐(2‐phenylethyl)furan ( 1 ) and 2‐methoxy‐4‐{[5‐(2‐phenylethyl)furan‐2‐yl]methyl}phenol ( 2 ), were synthesized starting from 2‐furaldehyde. A Wittig reaction of 2‐furaldehyde with benzyltriphenylphosphonium bromide followed by reduction of the alkene C?C bond with Mg gave 2‐(2‐phenylethyl)furan ( 5 ). Lithiation of 5 with BuLi at ?78° followed by alkylation with benzyl bromide gave natural product 1 . In another approach, Friedel? Crafts acylation of compound 5 with benzoyl chloride followed by deoxygenation of the C?O group afforded 1 . The natural product 2 was also synthesized by acylation of 5 with 4‐acetoxy‐3‐methoxybenzoyl chloride ( 16 ) followed by deoxygenation and deacetylation. 相似文献