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51.
The formation of host–guest complexes of cucurbit[7]uril (CB7) with the antihistamine drug tripelennamine (TRP) was studied by optical and NMR spectroscopy. The experimental and computational results are consistent with inclusion of a single TRP molecule in CB7. Addition of CB7 has tuned drug protonation states associated with (de)protonation of the ethyldimethylammonium and exocyclic nitrogens with an increase in the associated pKa values by 1.5 and 2.5 units, respectively. The incorporation of antihistamines drugs such as TRP in cucurbiturils could be utilized for switching their capability for selective binding to histamine H1‐receptors, in the future. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
52.
We report the first experimental violation of Bell's inequality in the spatial domain using the Einstein-Podolsky-Rosen state. Two-photon states generated via optical spontaneous parametric down-conversion are shown to be entangled in the parity of their one-dimensional transverse spatial profile. Superpositions of Bell states are prepared by manipulation of the optical pump's transverse spatial parity-a classical parameter. The Bell-operator measurements are made possible by devising simple optical arrangements that perform rotations in the one-dimensional spatial-parity space of each photon of an entangled pair and projective measurements onto a basis of even-odd functions. A Bell-operator value of 2.389+/-0.016 is recorded, a violation of the inequality by more than 24 standard deviations.  相似文献   
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54.
An ultra high performance liquid chromatography‐tandem mass spectrometric method has been developed for the highly sensitive and selective determination of regulated aflatoxins. The extraction of aflatoxins from baby food matrices were performed using liquid–liquid extraction procedure followed by immunoaffinity column cleanup. The higher sensitivity for the determination of target aflatoxins was fulfilled by applying a preconcentration step with immunoaffinity columns after acetonitrile–water extraction. The enhanced selectivity was attained with the triple quadrupole mass analyzer operated in electrospray positive ionization mode. Method validation was tested in five different baby food matrices by recovery experiments. Satisfactory recoveries, between 92 and 103%, with relative standard deviations lower than 8% were achieved in all the tested matrices. The proposed method was found to be specific as no interference peaks were observed for blank samples. The limit of detection of the method was found to be in the range of 0.003–0.008 ng/mL. The validated method was fruitfully applied to the screening of aflatoxins in baby foods and feeds sample retailed in local markets of Riyadh, Saudi Arabia. The obtained levels of all analyzed aflatoxins were below the regulation limits set by European Agency.  相似文献   
55.
Seaweeds can play a vital role in plant growth promotion. Two concentrations (5 and 10 mg/mL) of soluble polysaccharides extracted from the green macroalgae Ulva fasciata and Ulva lactuca were tested on Zea mays L. The carbohydrate and protein contents, and antioxidant activities (phenols, ascorbic, peroxidase, and catalase) were measured, as well as the protein banding patterns. The soluble polysaccharides at 5 mg/mL had the greatest effect on the base of all of the parameters. The highest effects of soluble polysaccharides on the Zea mays were 38.453, 96.76, 4, 835, 1.658, 7.462, and 38615.19, mg/mL for carbohydrates, proteins, phenol, µg ascorbic/mL, mg peroxidase/g dry tissue, and units/g tissue of catalase, respectively. The total number of protein bands (as determined by SDS PAGE) was not changed, but the density of the bands was correlated to the treatments. The highest band density and promoting effect were correlated to 5 mg/mL soluble polysaccharide treatments extracted from Ulva fasciata in Zea mays, which can be used as a biofertilizer.  相似文献   
56.
A novel conjugate of docetaxel and biotin (designated as IDD-1010) was designed and chemically synthesized via an ester linkage at position 2’ carbon in docetaxel. The synthesized pure IDD-1010 exhibits a potent anti-cancer activity in in vitro and in vivo studies. At 10 nM, IDD-1010 has induced increased apoptosis and mitotic arrest of PC3-Luc prostate cancer cells, causing aneuploidy and cell death at higher concentrations. Toxicology studies indicate that the maximal tolerated dose (MTD) of IDD-1010 is 150 mg/kg in mice; equivalent to about 12.2 mg/kg of body weight, or to about an 850 mg dose for a patient weighing 70 kg. The MTD-treated mice exhibited weight gain similar to that of the control group, with no gross pathological signs at 14 days post-dosing. At a lower dose, IDD-1010 treatment did not lead to any significant weight loss in mice, although decreased the tumor volume stemming from injecting cancer cells into the dorsal loop of mouse prostate, and it was found to be more potent than Paclitaxel (reference drug). Similarly, IDD-1010 treatment significantly reduced tumor weight and thereby increased the percentage of mice survival as compared to reference drug-treated and control groups. To summarize, the described experiments using IDD-1010, as compared to the reference drug, strongly suggest a potential treatment utility with a wider therapeutic window for prostate cancer. Henceforth, clinical research on such a novel drug candidate would be greatly worthwhile.  相似文献   
57.
Cost-effective separation of oil and immiscible organic contaminants from water has become an urgent challenge to protect aquatic and human life from devastating effects. Therefore, it has become imperative to develop super-selective materials for efficiently separating oil from water. In this work, a superhydrophobic surface has been formed that consists of a silane@polystyrene-coated polypropylene fibrous network (silane@PS-PPF) for efficient separation of accidentally spilled oil from water. The superhydrophobic PPFs were designed by a simple, cost-effective two-step process that includes photochemically controlled polymerization of styrene and subsequent dip coating in octadecyltrichlorosilane solution. The hydrophobic surface (CA=129°±4°) of the PS coated PPF after treating with silane was turned into a superhydrophobic body (CA=161°±2°). The achieved silane@PS-PPF fibrous network selectively allowed the fast permeation of the oils and non-polar organic liquids by altogether rejecting water during operation. The separation efficiency for various oils from the contaminated water was 96 to 99%, with a high flux in the range of 7606±312 L m−2h−1 to 9870±151 L m−2h−1. Apart from being used as a filter, the silane@PS-PPF was also used as an oil absorber and has shown an absorption capacity in the range of 1185 to 1535% for various oils. We anticipate that the developed silane@PS-PPF, due to its facile synthetic route, cost-effectiveness, and high performance, can be effectively used in oily wastewater treatment and clean-up of large oil spills from water.  相似文献   
58.
应用电化学法聚合酚藏花红(PPS)功能化的单壁碳纳米管,以其作为烟酰胺辅酶(NADH)氧化的电化学催化剂(电极),构建基于乙醇脱氢酶的安培型乙醇生物电化学传感器.该电极于0.0 V时,对NADH具有很好的催化性能.而单体酚藏花红则由于其电位过低(-0.48 V),不能显示催化性能.循环伏安和计时安培法测试表明:该传感器...  相似文献   
59.
Eight new photochromic dihydro 5-azaindolizines (DHAIs) linked with 2,5-diaryl-1,3,4-oxadiazole (OXD) derivatives containing terminal ethynes and butadiyne substituents on the fluorene part of the DHAI skeleton are synthesized via palladium-mediated coupling reaction pathways. Irradiation of the DHAI-OXD derivatives with polychromatic light affords red- and green-colored betaines.  相似文献   
60.
Multi‐addressable photophysical properties of new synthesized photochromic materials based on photochromic dihydroindolizine system (DHI) covalently linked to N‐acyl‐11 aminoundecanoic acid (AUDA) or to its sodium salt or to its ester, through an amidic or urethane linkage have been studied. The DHI skeleton in these compounds is substituted in both the fluorene part (region A) or in the heterocyclic base (region B) with the gelling moieties. These molecules have been designed to respond to their environment. Interestingly, they are shown to act as efficient gelators for polar organic fluids, water and obviously they exhibit a thermosensitive answer as low molecular mass organogelators. In these fluids, the aggregative properties are totally suppressed upon conversion to neutral carboxylic species. The gels of these carboxylate sodium salts are shown to be markedly affected by light irradiation. Supramolecular gelating assemblies can be disrupted by the photoinduced ring opening of the DHI subunit, so that the macroscopic flowing property is recovered. Upon a further thermal treatment, the system is reversibly converted back to the supramolecular network. Controlled gelation could be achieved using temperature, light, or acidity as external stimuli. These new synthesized photochromic gels with their multi‐addressable properties will find their applications as super photoresponsive materials. Developing and tuning of the photophysical properties of the synthesized compounds by the amide and urethane substituents in the 4‐position of the fluorene and pyridazine regions have been achieved. The absorption maxima (λmax) and the half‐lives (t1/2) of the colored betaines were detected in all cases using UV/VIS spectrophotometric measurements. Irradiation of DHI 12‐20 in CH2Cl2 or in acetonitrile solutions at ambient temperature with polychromatic light leads to the formation of red to red‐violet colored betaines 12 ′ ‐20 ′. The kinetics of the bleaching process of betaines 12 ′ ‐20 ′ to DHIs 12‐20 were found to take place in the second range (96‐218 s) and fit well the first order thermal back reaction. Some of these DHIs showed a photostability higher than that of the standard one. These interesting photophysical properties will help this family of compounds to find useful applications. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
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