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191.
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Increased oxidative stress in metabolic complications like type 2 diabetes, dyslipidemia and cardiovascular disorders exerts potential health hazards in many facets. Enhanced production of reactive oxygen species (ROS) due to increased oxidative stress promotes the damage of many biologically important macromolecules. Hypochlorous acid (HOCl), a microbicidal agent is also known to be an important ROS sub-species. An enhanced generation of endogenous HOCl due to diseased condition therefore can be detrimental to health. In present work, a new quinoline-diaminomaleonitrile based probe (HQMN) has been designed for the selective detection of hypochlorite. The probe in hand shows a selective ratiometric emission change towards OCl?. The probe behaves as a highly selective and sensitive tool for the detection of OCl? over other analytes with a fast response time (within 100 s). Bioimaging study revealed that HQMN can detect endogenous OCl? in human monocytes and an increase in endogenous HOCl concentration has been witnessed in diabetic condition compared to healthy control. Thus HQMN can be used as an excellent fluorescent probe for dynamic tracking of hypochorite in living biological cells especially to identify diabetic conditions.  相似文献   
194.

Operations research (OR) has been at the core of decision making since World War II, and today, business interactions on different platforms have changed business dynamics, introducing a high degree of uncertainty. To have a sustainable vision of their business, firms need to have a suitable decision-making process at each stage, including minute details. Our study reviews and investigates the existing research in the field of decision support systems (DSSs) and how artificial intelligence (AI) capabilities have been integrated into OR. The findings of our review show how AI has contributed to decision making in the operations research field. This review presents synergies, differences, and overlaps in AI, DSSs, and OR. Furthermore, a clarification of the literature based on the approaches adopted to develop the DSS is presented along with the underlying theories. The classification has been primarily divided into two categories, i.e. theory building and application-based approaches, along with taxonomies based on the AI, DSS, and OR areas. In this review, past studies were calibrated according to prognostic capability, exploitation of large data sets, number of factors considered, development of learning capability, and validation in the decision-making framework. This paper presents gaps and future research opportunities concerning prediction and learning, decision making and optimization in view of intelligent decision making in today’s era of uncertainty. The theoretical and managerial implications are set forth in the discussion section justifying the research questions.

  相似文献   
195.
The performance of a recently proposed scaled one-electron Hamiltonian (SOEH ) model is tested against parallel sets of restricted open-shell calculations by the method of Roothaan. It is found that the energy calculated by SOEH model, in general, lies slightly higher than the energy computed by the restricted open-shell method of Roothaan lending credibility to the application of variational argument to the scaled pseudoenergy functional (Eav) for deriving the SOEH model. The numerical stability of the converged SOEH energy with respect to changes in trial vectors indicates the reliability of the method. The SOEH model is shown to perform well in the calculation of geometries of radicals and ions. The convergence behavior of the SOEH model is compared with that of the restricted open-shell method of Roothaan.  相似文献   
196.
The performance of the VN—1 potential model at the INDO/2 level of approximation in the calculation of transition energy, singlet—triplet splitting, change in molecular structure, inversion barrier and electron-density distribution in the excited electronic states of a few simple carbonyls is analysed. The method turns out to be reasonably successful in many ways.  相似文献   
197.
Amino groups are one of the various types of hydrogen bond donors, abundantly found in protein main chains, protein side chains, and DNA bases. The polar hydrogen atoms of these groups exhibit short ranged, specific, and directional hydrogen bonds, which play a decisive role in the specificity and stability of protein-DNA complexes. To date, planar amino groups are only considered for the analysis of protein-DNA interfacial hydrogen bonds. This assumption regarding hydrogen atom positions possibly failed to establish the expected role of hydrogen bonds in protein-DNA recognition. We have performed ab initio quantum chemical studies on amino acid side chains and DNA bases containing amino groups as well as on specific hydrogen bonded residue pairs selected from high-resolution protein-DNA complex crystal structures. Our results suggest that occurrences of pyramidal amino groups are more probable in comparison with the usually adopted planar geometry. This increases the quality of the existing hydrogen bonds in almost all cases. Further, detailed analysis of protein-DNA interfacial hydrogen bonds in 107 crystal structures using the in-house program "pyrHBfind" indicates that consideration of energetically more preferred nonplanar amino groups improves the geometry of hydrogen bonds and also gives rise to new contacts amounting to nearly 14.5% of the existing interactions. Large improvements have been observed specifically for the amino groups of guanine, which faces the DNA minor groove and thus helps to resolve the problem of insufficient directional contacts observed in many minor groove binding complexes. Apart from guanine, improvement observed for asparagine, glutamine, adenine, or cytosine also indicates that the consideration of nonplanar amino groups leads to a more realistic scenario of hydrogen bonds occurring between protein and DNA residues.  相似文献   
198.
Reactions of carbonate radical (CO3 ), generated by photolysis or by radiolysis of a carbonate solution with nickel(II)-iminodiacetate (Ni(II)IDA) were studied at pH 10.5 and ionic strength (I)==0.2 mol·dm–3. The stable product arising from the ligand degradation in the complex is mainly glyxalic acid. Time-resolved spectroscopy and transient kinetics were studied using flash photolysis. From the kinetic data it was suggested that the carbonate radical initially reacts with Ni(III)IDA with a rate constant (2.4±0.4)·106 dm3·mol–1·s–1 to form a Ni(II)IDA species which, however, undergoes a first-order transformation (k=2.7·102·s–1) to give a radical intermediate of the type Ni(II)RNHCHCO 2 ) which rapidly forms an adduct containing a Ni–C bond. This adduct decays very slowly to give rise to glyoxalic acid. From a consideration of equilibrium between Ni(II)IDA and Ni(III)IDA, the one electron reduction potential for the Ni(III)IDA/Ni(II)IDA couple was determined to be 1.467 V.  相似文献   
199.
The spectra of cosmic pions and nucleons at an atmospheric depth of 100 g cm?2 have been derived from sea level muon spectra at low and high latitudes. The derived spectra of pions and nucleons at low and high latitudes follow the relations N(Eπ) dEπ = 0.23 Eπ?2.68dEπ and N(Ep) dEp = 2.98 E dEp per cm2 sec str GeV in the energy range 15–1200 GeV. Below 15 GeV it is found that the exponent of the energy spectrum is very much dependent upon the incident energy and latitude of the location. The major difference between low and high latitude pion spectra can be explained in terms of geomagnetic effects.  相似文献   
200.
Reactions of carbonate (CO 3 –· ) and bicarbonate (HCO 3 · ) radicals generated by photolysis of a carbonate or bicarbonate solution at pH 11.2 and 8.5, respectively, with Co(II) complexes of iminodiacetic acid (IDA) and ethylenediaminetetraacetic acid (EDTA) have been studied. The rate constants for the reactions were in the order of 106–107 dm3mol–1s–1. From the time-resolved spectroscopy of the products formed after reaction of CO –· or HCO 3 · , it is observed that CO 3 –· or HCO 3 · oxidize the metal center to its higher oxidation state.  相似文献   
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