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931.
Shaik Thaslim Basha Hasti Sudhamani Syed Rasheed Nagam Venkateswarlu Tartte Vijaya 《Phosphorus, sulfur, and silicon and the related elements》2016,191(10):1339-1343
A series of diethyl/ethylphenyl {2-(benzo[d]thiazol-2-yl)phenylamino}phosphonates and phosphinates were synthesized under microwave irradiation and neat conditions via Kabachnik-Fields reaction in high yields (80%–93%). The compounds were screened for antimicrobial and antioxidant properties. A few compounds showed effective antibacterial and antifungal activities at MIC value 12.5 μg/mL as compared with the standard at MIC value 6.25 μg/mL. 相似文献
932.
Amjad Hussain Achyut Adhikari Syed Abdulmajid Ayatollahi Atta-ur-Rahman 《Natural product research》2016,30(13):1511-1516
A new adduct of abietane-type diterpene, salvialeriicone (1), was isolated from Salvia leriifolia Benth., along with a new chemical entity nor-abietane diterpene, 2-isopropyl-8,8-dimethyl-7,8-dihydrophenanthrene-1,4,5(6H)-trione (2). Their structures were determined using mass spectrometry, and 1D- and 2D-NMR spectroscopy. 相似文献
933.
Air and water velocity fields have been simulated during natural convection, using a two-dimensional volume of fluid (VOF)
model. The results have shown that during unstable thermal stratification, the root-mean-square (RMS) airside velocities are
an order of magnitude higher than the RMS waterside velocities, whereas, during the stable thermal stratification, the velocity
magnitudes are comparable for air and water sides. Furthermore, the magnitude of the air velocity changed more rapidly with
the change in the bulk air–water temperature difference than the water velocity, indicating that the air velocities are more
sensitive to the bulk air and water temperature difference than the water velocities. A physical model of the heat and mass
transfer across the air–water interface is defined. According to this model, the vortices on the air and water sides play
an important role in enhancing the heat and mass transfer. Due to the significance of the flow velocities in the transport
process, it has been proposed that the correlations for the heat and mass transfer during natural convection should be improved
by incorporating the flow velocity as a parameter. 相似文献
934.
Dae-Young?Kim Surendra?Shinde Rijuta?Saratale Asad?Syed Fuad?Ameen Gajanan?GhodakeEmail authorView authors OrcID profile 《Mikrochimica acta》2017,184(12):4695-4704
The preparation and application of casein-capped gold nanoparticles (AuNPs) as a specific probe for ferric ions Fe(III) is reported. The functionalized AuNPs exhibit narrow size distribution and form stable dispersions in water of different ionic strengths and basicity. The presence of diverse functional groups from the side chain of peptides warrants colloidal stability of AuNPs and also assists recognition of Fe(III) in versatile conditions. Fe(III) ion reportedly causes the aggregation of AuNPs and a red-shift in absorbance toward longer wavelength (660 nm). A spectrophotometric method is appropriate for selective detection of Fe(III) and the spectral shift is also accompanied by a color change from red to blue. The aggregation of AuNPs is not suppressed after the addition of NaOH or at moderate ionic strength. The resulting spectrophotometric method works for Fe(III) in the concentration range of 0.1 to 0.9 μM and has a detection limit of 450 nM. The AuNP probe can also detect Fe(III) ion content in real samples at the same detection limit, which is much lower than the maximum contaminant level allowed for Fe(III) in drinking water (5.37 μM) by the U.S. Environmental Protection Agency. 相似文献
935.
Syed Lal Badshah Anila Riaz Akhtar Muhammad Gülsen Tel ayan Fatih ayan Mehmet Emin Duru Nasir Ahmad Abdul-Hamid Emwas Mariusz Jaremko 《Molecules (Basel, Switzerland)》2021,26(5)
Mushroom polysaccharides are active medicinal compounds that possess immune-modulatory and anticancer properties. Currently, the mushroom polysaccharides krestin, lentinan, and polysaccharopeptides are used as anticancer drugs. They are an unexplored source of natural products with huge potential in both the medicinal and nutraceutical industries. The northern parts of Pakistan have a rich biodiversity of mushrooms that grow during different seasons of the year. Here we selected an edible Morchella esculenta (true morels) of the Ascomycota group for polysaccharide isolation and characterization. Polysaccharopeptides and polysaccharides from this mushroom were isolated using the green chemistry, hot water treatment method. Fourier transform infrared spectroscopy revealed the sugar nature and possible beta-glucan type structure of these polysaccharides. Antioxidant assays showed that the deproteinized polysaccharides have moderate free radical scavenging activity. These isolated polysaccharides exhibited good acetylcholinesterase (AChE) and butyryl cholinesterase (BChE) inhibition activities. Therefore, these polysaccharides may be valuable for the treatment of Alzheimer’s and Parkinson’s diseases. Further bioassays are needed to discover the true potential of M. esculenta polysaccharides for medicinal purposes. 相似文献
936.
Shwetha U R Rajith Kumar C R Kiran M S Virupaxappa S. Betageri Latha M S Ravindra Veerapur Ghada Lamraoui Abdulaziz A. Al-Kheraif Abdallah M. Elgorban Asad Syed Chandan Shivamallu Shiva Prasad Kollur 《Molecules (Basel, Switzerland)》2021,26(9)
Nanoworld is an attractive sphere with the potential to explore novel nanomaterials with valuable applications in medicinal science. Herein, we report an efficient and ecofriendly approach for the synthesis of Nickel oxide nanoparticles (NiO NPs) via a solution combustion method using Areca catechu leaf extract. As-prepared NiO NPs were characterized using various analytical tools such as powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and UV-Visible spectroscopy (UV-Vis). XRD analysis illustrates that synthesized NiO NPs are hexagonal structured crystallites with an average size of 5.46 nm and a hexagonal-shaped morphology with slight agglomeration. The morphology, size, and shape of the obtained material was further confirmed using SEM and TEM analysis. In addition, as-prepared NiO NPs have shown potential antidiabetic and anticancer properties. Our results suggest that the inhibition of α-amylase enzyme with IC 50 value 268.13 µg/mL may be one of the feasible ways through which the NiO NPs exert their hypoglycemic effect. Furthermore, cytotoxic activity performed using NiO NPs exhibited against human lung cancer cell line (A549) proved that the prepared NiO NPs have significant anticancer activity with 93.349 μg/mL at 50% inhibition concentration. The biological assay results revealed that NiO NPs exhibited significant cytotoxicity against human lung cancer cell line (A549) in a dose-dependent manner from 0–100 μg/mL, showing considerable cell viability. Further, the systematic approach deliberates the NiO NPs as a function of phenolic extracts of A. catechu with vast potential for many biological and biomedical applications. 相似文献
937.
Syed Shaheen Shah Md. Abdul Aziz Munetaka Oyama Abdul‐Rahman F. Al‐Betar 《Chemical record (New York, N.Y.)》2021,21(1):204-238
Due to their potential applications in industry and potent toxicity to the environment, sulfides and their detection have attracted the attention of researchers. To date, a large number of controlled‐potential techniques for electrochemical sulfide sensors have been developed, thanks to their simplicity, reasonable limit of detection (LOD), and good selectivity. Different researchers have applied different strategies for developing selective and sensitive sulfide sensors. However, there has been no systematic review on controlled‐potential techniques for sulfide sensing. In light of this absence, the main aim of this review article is to summarize various strategies for detecting sulfide in different media. The efficiencies of the developed sulfide sensors for detecting sulfide in its various forms are determined, and the essential parameters, including sensing strategies, working electrodes, detection media, pH, LOD, sensitivity, and linear detection range, are emphasized in particular. Future research in this area is also recommended. It is expected that this review will act as a basis for further research on the fabrication of sulfide sensors for practical applications. 相似文献
938.
The pooling layer is at the heart of every convolutional neural network (CNN) contributing to the invariance of data variation. This paper proposes a pooling method based on Zeckendorf’s number series. The maximum pooling layers are replaced with Z pooling layer, which capture texels from input images, convolution layers, etc. It is shown that Z pooling properties are better adapted to segmentation tasks than other pooling functions. The method was evaluated on a traditional image segmentation task and on a dense labeling task carried out with a series of deep learning architectures in which the usual maximum pooling layers were altered to use the proposed pooling mechanism. Not only does it arbitrarily increase the receptive field in a parameterless fashion but it can better tolerate rotations since the pooling layers are independent of the geometric arrangement or sizes of the image regions. Different combinations of pooling operations produce images capable of emphasizing low/high frequencies, extract ultrametric contours, etc. 相似文献
939.
In this article, a synchronization problem for master-slave Markovian switching complex dynamical networks with time-varying delays in nonlinear function via sliding mode control is investigated. On the basis of the appropriate Lyapunov-Krasovskii functional, introducing some free weighting matrices, new synchronization criteria are derived in terms of linear matrix inequalities (LMIs). Then, an integral sliding surface is designed to guarantee synchronization of master-slave Markovian switching complex dynamical networks, and the suitable controller is synthesized to ensure that the trajectory of the closed-loop error system can be driven onto the prescribed sliding mode surface. By using Dynkin's formula, we established the stochastic stablity of master-slave system. Finally, numerical example is provided to demonstrate the effectiveness of the obtained theoretical results. 相似文献
940.
Globally, metformin hydrochloride (HCl) is the most commonly used antidiabetic drug and provides safe medication because of low risk of the side effects (lactic acidosis). Therefore, various researches have been established in pharmacodynamics and pharmacokinetic studies using various analytical applications such as calorimetry, spectrophotometry, and chromatography. But the chromatographic techniques are most widely used methods for the analysis of metformin HCl. This review discussed the different chromatographic methods used for the analysis of metformin HCl and its sample preparation for the isolation in different biological and environmental samples. Moreover, the mechanism for the fragmentation of ion products in LC–MS/MS is indicated for high throughput of the methods involved in the determination of metformin HCl in various sample matrices. The advancement in the chromatographic modalities provides the wide range of assays discussed herein. 相似文献