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81.
Jing Li Suan Shi Maobing Tu Brain Via Fubao Fuelbio Sun Sushil Adhikari 《Applied biochemistry and biotechnology》2018,186(3):662-680
Bioconversion of lignocellulose to biofuels suffers from the degradation compounds formed during pretreatment and acid hydrolysis. In order to achieve an efficient biomass to biofuel conversion, detoxification is often required before enzymatic hydrolysis and microbial fermentation. Prehydrolysates from ethanol organosolv-pretreated pine wood were used as substrates in butanol fermentation in this study. Six detoxification approaches were studied and compared, including overliming, anion exchange resin, nonionic resin, laccase, activated carbon, and cysteine. It was observed that detoxification by anion exchange resin was the most effective method. The final butanol yield after anion exchange resin treatment was comparable to the control group, but the fermentation was delayed for 72 h. The addition of Ca(OH)2 was found to alleviate this delay and improve the fermentation efficiency. The combination of Ca(OH)2 and anion exchange resin resulted in completion of fermentation within 72 h and acetone–butanol–ethanol (ABE) production of 11.11 g/L, corresponding to a yield of 0.21 g/g sugar. The cysteine detoxification also resulted in good detoxification performance, but promoted fermentation towards acid production (8.90 g/L). The effect of salt on ABE fermentation was assessed and the possible role of Ca(OH)2 was to remove the salts in the prehydrolysates by precipitation. 相似文献
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Panchanan Puzari Biplab Sarkar Satrajit Adhikari 《International journal of quantum chemistry》2005,105(3):209-224
The time‐dependent discrete variable representation (TDDVR) of a wave function with grid points defined by the Hermite part of the Gauss–Hermite (G‐H) basis set introduces quantum corrections to classical mechanics. The grid points in this method follow classical trajectory and the approach converges to the exact quantum formulation with sufficient trajectories (TDDVR points) but just with a single grid point; only classical mechanics performs the dynamics. This newly formulated approach (developed for handling time‐dependent molecular quantum dynamics) has been explored to calculate vibrational transitions in the inelastic scattering processes. Traditional quantum mechanical results exhibit an excellent agreement with TDDVR profiles during the entire propagation when enough grid points are included in the quantum‐classical dynamics. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005 相似文献
85.
Selective Control of HOD photodissociation has been investigated using simple field profiles. Initial results indicate that preferential dissociation of O–H bond may be achieved from the ground vibrational state and that the O–D bond can be selectively dissociated using only the fundamental excitation in this mode. Dissociation from 2 quanta of excitation in the O–D mode produces 82.8% products with O–D bond dissociation. Preferential maximization of O–D dissociation vis-à-vis O–H bond may also be achieved from the ground vibrational state using a combination of two lasers with carrier frequencies 54920 cm−1 and 52203 cm−1. The use of Field Optimized Initial STate (FOIST) based scheme to enhance selective control of HOD photodissociation provides additional 6 − 8% H–O + D products compared to those obtained without FOIST. 相似文献
86.
[reaction: see text] A new synthesis of enantiopure 3,3-disubstituted oxindoles by stereoselective Mukaiyama aldol reaction of 3-substituted 2-siloxyindoles and chiral, enantiopure aldehydes having nitrogen or oxygen substituents at the alpha carbon is described. When the C3 substituent of the prochiral nucleophile is aryl or heteroaryl, stereoselectivity is high (10-80:1). 相似文献
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Gold-catalyzed glycosylation using S-but-3-ynyl and gem-dimethyl S-but-3-ynyl thioglycoside donors has been investigated for the synthesis of various types of complex oligosaccharides. It was found that 2,2-dimethyl S-but-3-ynyl thioglycoside donors are more reactive than their S-but-3-ynyl thioglycoside counterparts and gave the glycoside products in relatively higher yields. 相似文献
89.
The thermodynamic properties such as, free energy of mixing (GM), heat of mixing (HM), entropy of mixing (SM) and microscopic properties such as, concentration fluctuation in long wavelength limit (SCC(0)), Warren–Cowely short range ordering parameter (α1), ratio of mutual and intrinsic diffusion coefficients (DM/Did) of two Cd-based liquid alloys have been studied by using two different models. The properties of Cd–Hg liquid alloy at 600 K have been studied on the basis of regular solution model, and the properties of Cd–Na liquid alloy at 673 K have been studied on the basis of quasi-chemical expression for weakly interacting system. 相似文献
90.
Synthesis,structural and chemosensitivity studies of arene d6 metal complexes having N‐phenyl‐N´‐(pyridyl/pyrimidyl)thiourea derivatives
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Sanjay Adhikari Omar Hussain Roger M. Phillips Werner Kaminsky Mohan Rao Kollipara 《应用有机金属化学》2018,32(6)
The d6 metal complexes of thiourea derivatives were synthesized to investigate its cytotoxicity. Treatment of various N‐phenyl‐N´ pyridyl/pyrimidyl thiourea ligands with half‐sandwich d6 metal precursors yielded a series of cationic complexes. Reactions of ligand (L1‐L3) with [(p‐cymene)RuCl2]2 and [Cp*MCl2]2 (M = Rh/Ir) led to the formation of a series of cationic complexes bearing general formula [(arene)M(L1)к2(N,S)Cl]+, [(arene)M(L2)к2(N,S)Cl]+ and [(arene)M(L3)к2(N,S)Cl]+ [arene = p‐cymene, M = Ru ( 1 , 4 , 7 ); Cp*, M = Rh ( 2 , 5 , 8 ); Cp*, Ir ( 3 , 6 , 9 )]. These compounds were isolated as their chloride salts. X‐ray crystallographic studies of the complexes revealed the coordination of the ligands to the metal in a bidentate chelating N,S‐ manner. Further the cytotoxicity studies of the thiourea derivatives and its complexes evaluated against HCT‐116 (human colorectal cancer), MIA‐PaCa‐2 (human pancreatic cancer) and ARPE‐19 (non‐cancer retinal epithelium) cancer cell lines showed that the thiourea ligands displayed no activity. Upon complexation however, the metal compounds possesses cytotoxicity and whilst potency is less than cisplatin, several complexes exhibited greater selectivity for HCT‐116 or MIA‐PaCa‐2 cells compared to ARPE‐19 cells than cisplatin in vitro. Rhodium complexes of thiourea derivatives were found to be more potent as compared to ruthenium and iridium complexes. 相似文献