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621.
《Arabian Journal of Chemistry》2022,15(5):103756
Heterocyclic compounds occupy an important position in chemistry because of their wide range of uses in drug design, photochemistry, agrochemicals, and other fields. Indole and indazole scaffolds are available from natural and synthetic sources, and molecules containing these scaffolds have been shown to have various biological effects, including anti-inflammatory, antibacterial, antiviral, antifungal, analgesic, anticancer, antioxidant, anticonvulsant, antidepressant, and antihypertensive activities. Indole and indazole molecules bind to receptors with high affinity, and thus are useful for the study of bioactive compounds involved in multiple pathways. In this review, we highlight the antihypertensive activity and the mechanisms of action of indole and indazole derivatives. In addition, structure–activity relationship studies of the antihypertensive effect are presented. 相似文献
622.
623.
Benjamin Zimmerman Payel Kundu William D. Rooney Jacob Raber 《Molecules (Basel, Switzerland)》2021,26(11)
In both humans and animal models, consumption of a high-saturated-fat diet has been linked to vascular dysfunction and cognitive impairments. Laboratory animals provide excellent models for more invasive high-fat-diet-related research. However, the physiological differences between humans and common animal models in terms of how they react metabolically to high-fat diets need to be considered. Here, we review the factors that may affect the translatability of mechanistic research in animal models, paying special attention to the effects of a high-fat diet on vascular outcomes. We draw attention to the dissociation between metabolic syndrome and dyslipidemia in rodents, unlike the state in humans, where the two commonly occur. We also discuss the differential vulnerability between species to the metabolic and vascular effects of macronutrients in the diet. Findings from animal studies are better interpreted as modeling specific aspects of dysfunction. We conclude that the differences between species provide an opportunity to explore why some species are protected from the detrimental aspects of high-fat-diet-induced dysfunction, and to translate these findings into benefits for human health. 相似文献
624.
Xiuli Qu Ronald L. Rardin Julie Ann S. Williams Deanna R. Willis 《European Journal of Operational Research》2007
Advanced access scheduling, introduced in the early 1990s, is reported to significantly improve the performance of outpatient clinics. The successful implementation of advanced access scheduling requires the match of daily healthcare provider capacity with patient demand. In this paper, for the first time a closed-form approach is presented to determine the optimal percentage of open-access appointments to match daily provider capacity to demand. This paper introduces the conditions for the optimal percentage of open-access appointments and the procedure to find the optimal percentage. Furthermore, the sensitivity of the optimal percentage of open-access appointments to provider capacity, no-show rates, and demand distribution is investigated. Our results demonstrate that the optimal percentage of open-access appointments mainly depends on the ratio of the average demand for open-access appointments to provider capacity and the ratio of the show-up rates for prescheduled and open-access appointments. 相似文献
625.
A model for quantifying the performance of acoustic emission (AE) systems on plate-like structures is presented. Employing a linear transfer function approach the model is applicable to both isotropic and anisotropic materials.The model requires several inputs including source waveforms, phase velocity and attenuation. It is recognised that these variables may not be readily available, thus efficient measurement techniques are presented for obtaining phase velocity and attenuation in a form that can be exploited directly in the model. Inspired by previously documented methods, the application of these techniques is examined and some important implications for propagation characterisation in plates are discussed. Example measurements are made on isotropic and anisotropic plates and, where possible, comparisons with numerical solutions are made.By inputting experimentally obtained data into the model, quantitative system metrics are examined for different threshold values and sensor locations. By producing plots describing areas of hit success and source location error, the ability to measure the performance of different AE system configurations is demonstrated. This quantitative approach will help to place AE testing on a more solid foundation, underpinning its use in industrial AE applications. 相似文献
626.
Xiaoshan Zhu Lin Zhu Yongsheng Chen Shengyan Tian 《Journal of nanoparticle research》2009,11(1):67-75
The rapid growth of nanotechnology is stimulating research on the potential environmental impacts of manufactured nanomaterials
(MNMs). This paper summarizes a comprehensive study on the 48-h acute toxicity of water suspensions of six MNMs (i.e., ZnO,
TiO2, Al2O3, C60, SWCNTs, and MWCNTs) to Daphnia magna, using immobilization and mortality as toxicological endpoints. The results show that the acute toxicities of all MNMs tested
are dose dependent. The EC50 values for immobilization ranged from 0.622 mg/L (ZnO NPs) to 114.357 mg/L (Al2O3 NPs), while the LC50 values for mortality ranged from 1.511 mg/L (ZnO NPs) to 162.392 mg/L (Al2O3 NPs). In these tests, TiO2, Al2O3, and carbon-based nanomaterials were more toxic than their bulk counterparts. Moreover, D. magna were found to ingest nanomaterials from the test solutions through feeding behaviors, which indicates that the potential
ecotoxicities and environmental health effects of these MNMs cannot be neglected. 相似文献
627.
Photocatalytic reduction of chromium(VI) in aqueous solution using dye-sensitized nanoscale ZnO under visible light irradiation 总被引:1,自引:0,他引:1
Photocatalytic removal of Cr6+ from aqueous solution using dye-sensitized nanoscale ZnO under visible light irradiation was studied in this work. First,
nanoscale ZnO was prepared by the co-precipitation method. Then, sensitization of nanoscale ZnO by Alizarin Red S dye followed.
Further, nanoscale ZnO and dye-sensitized nanoscale ZnO (designated nanoZnO and nanoZnO*, respectively) were both characterized
by various photospectrometry methods, such as scanning electron microscopy (SEM), scanning electron microscopy-energy dispersive
X-ray spectrometry (SEM-EDS), EDS-mapping, transmission electron microscopy (TEM), and X-ray diffractometry (XRD). It was
found that both types of prepared particles are spherical in shape with a size range of 20 to 50 nm. XRD patterns showed that
both nanoZnO and nanoZnO* had the same crystalline structure of zincite. In the photocatalytic reduction aspect, effects of
different light sources and dosage of nanoZnO* on Cr6+ reduction ([Cr6+]initial = 20 mg/L) were evaluated in this work. Treatment of chromium(VI)-bearing wastewater under the conditions of using 1.0 g/L
of nanoZnO*, neutral pH, irradiation of household fluorescence lamps for 6 h and 17 h would yield Cr6+ removal efficiencies of about 68% and 90%, respectively. When the household fluorescence lamps were replaced by visible-light
lamps of 400–500 nm in wavelength, the corresponding removal efficiencies dropped to about 50% and 75%, respectively. When
nanoZnO* was irradiated by sunlight under almost the same experimental conditions, the Cr6+ reduction efficiency increased up to 90%. In summary, sensitizing nanoscale ZnO with Alizarin Red S dye for photocatalytic
applications using visible light is feasible. The relevant reaction mechanism and pathways were also proposed in this work. 相似文献
628.
629.
本文参考有关文献,详细论述了废水处理技术在明胶生产废水治理中的应用与发展.在分析明胶废水污染现状、废水水质特性的基础上,从混凝、生物处理、清洁生产、超滤膜处理、污泥处理、蛋白质回收、环境健康研究几个方面综述了迄今为止围绕明胶生产废水治理所开展的有关研究工作和治理技术. 相似文献
630.
靳争京 《广东微量元素科学》2001,8(5):58-59
对18种保健食品进行了连续3个月的稳定性测试结果表明,所测产品理化性能稳定,微生物及感官指标合格,并提出了建议。 相似文献