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91.
In this paper, we present the impact of swift heavy ion beam irradiation on the structural, optical and electronic properties of SnO2 thin films. Thin films were deposited using the pulsed laser deposition technique on Al2O3 substrates. Atomic force microscopy, X-ray diffraction, UV–visible absorption and temperature-dependent resistivity measurements were performed to explore the morphological, structural, optical and electronic properties of the as-deposited and irradiated samples. The peak intensity of the (200) peak was found to decrease monotonously with increasing irradiation fluence. The band gap energy of the 1×1011 ion/cm2 irradiated sample was found to increase. The electrical resistivity of the samples showed a continuous increase with the irradiation fluence.  相似文献   
92.
Mahayograj Guggul is an ancient ayurvedic medicine, prescribed for various joint disorders like arthritis, gout, and rheumatism. The present research was envisaged to develop a simple, sensitive, and comprehensive analytical method for standardization of Mahayograj Guggul. The analysis was conducted for gallic acid, protocatechuic acid, vanillic acid, cinnamic acid, piperine, guggulsterone-E, and guggulsterone-Z by high-performance thin-layer chromatography, and additionally ferulic acid, ellagic acid, and picroside I by ultra high-performance liquid chromatography. These developed methods were validated as per international guidelines, and were found linear (r> 0.99), sensitive, precise (relative standard deviation < 5%), and accurate with recovery values (85–105%). The limit of detection and quantification were in the range of 0.11–23.6 and 0.33–71.51 μg/g. Gas chromatography tandem mass spectrometry was used to develop Mahayograj Guggul fingerprinting profile and to identify mid-polar or nonpolar compounds. Proximate analysis was used to ascertain the functional groups present in Mahayograj Guggul. Ultra high-performance liquid chromatography and gas chromatography tandem mass spectrometry were further employed to authenticate quality reproducibility in the active ingredients of Mahayograj Guggul in six commercial batches. Taken together, these analytical methods provide a scientific basis and reference for quality control evaluation of Mahayograj Guggul and similar traditional broad-spectrum formulations.  相似文献   
93.
Individuals with diabetic foot ulcers have overlapped the inflammatory, proliferative and remodeling phase, making the tissue vulnerable to delayed healing responses. We aimed to establish the dose–response relationship of photobiomodulation therapy of different doses and matrix metalloproteinases in the healing dynamics of diabetic neuropathic ulcers. Diabetes was induced in 126 Albino Wistar rats, and neuropathy was induced to the hind paw by a sciatic nerve injury method. An excisional wound was created on the neuropathy-induced leg. Photobiomodulation therapy of dosages 4, 6, 8, 10, 12 and 15 J cm−2 and wavelength 655 nm and 808 nm was irradiated. Photobiomodulation therapy of dosages 4, 6 and 8 J cm−2 showed better wound healing properties with optimized levels of matrix metalloproteinases-1 and 8. We observed a strong dose response in the experimental group treated with 6 and 8 J cm−2. The findings from the present study conclude that photobiomodulation therapy of dosages 4, 6 and 8 J cm−2 is suggestive of usefulness in diabetic neuropathic ulcer healing. Markers like matrix metalloproteinases may give a clear direction on response to the therapy. Based on the findings from the present study, we recommend to validate the findings for safety and efficacy in future through human prospective randomized controlled clinical trials.  相似文献   
94.
A ‘one pot’ synthesis of 2‐aryl‐4H‐1‐benzopyran‐4‐ones (3a‐3f) is being reported. A mixture of o‐hydroxyacetophenone, aroyl chloride, powdered n‐tetrabutylammonium hydrogensulphate (n‐TBAHSO4) and potassium hydroxide (KOH) were either irradiated by microwaves or sonicated in an ultrasonic cleaning bath to afford flavones directly. On the contrary, conventional liquid‐liquid Phase Transfer Catalysis (PTC) using benzene as organic phase and aqueous KOH as the second phase afforded first β‐diketones in accordance with Baker‐Venkataraman synthesis which upon cyclization by p‐toluenesulphonic acid (p‐TSA) gave desired flavones in the next step. PTC coupled with microwaves or ultrasound show enhanced yields, the clean reaction conditions require less time, and have easier workup protocol. All synthesized compounds were characterized by their Proton Magnetic Resonance (PMR), IR, FAB Mass and elemental analyses.  相似文献   
95.
Abstract —Reaction of bis(triorganotin)oxide with Schiff bases derived by condensation of heterocyclic ketones, 2-acetylfuran and 2-acetylthiophene, with various sulfadrugs (sulfaguanidine, sulfathiazole, sulfisoxazole and sulfadiazine) leads to the formation of a new series of organotin(IV) complexes. An attempt has been made to probe their structures on the basis of elemental analysis, conductance measurements, molecular weight determination, UV, IR and NMR (1H, 13C and 119Sn) spectral studies. The results of antimicrobial effects of some representative complexes on different species of pathogenic fungi and bacteria have also been recorded and discussed.  相似文献   
96.
In stratified sampling when strata weights are unknown double sampling technique may be used to estimate them. At first a large simple random sample from the population without considering the stratification is drawn and sampled units belonging to each stratum are recorded to estimate the unknown strata weights. A stratified random sample is then obtained comprising of simple random subsamples out of the previously selected units of the strata. If the problem of non-response is there, then these subsamples may be divided into classes of respondents and non-respondents. A second subsample is then drawn out of non-respondents and an attempt is made to obtain the information. This procedure is called Double Sampling for Stratification (DSS). Okafor (Aligarh J Statist 14:13–23, 1994) derived DSS estimators based on the subsampling of non-respondents. Najmussehar and Bari (Aligarh J Statist 22:27–41, 2002) discussed an optimum double sampling design by formulating the problem as a mathematical programming problem and used the dynamic programming technique to solve it. In the present paper a multivariate stratified population is considered with unknown strata weights and an optimum sampling design is proposed in the presence of non-response to estimate the unknown population means using DSS strategy. The problem turns out to be a multiobjective integer nonlinear programming problem. A solution procedure is developed using Goal Programming technique. A numerical example is presented to illustrate the computational details.  相似文献   
97.
Thomson scattering technique based on high power laser has already proved its superoirity in measuring the electron temperature (T e and density (n e) in fusion plasma devices like tokamaks. The method is a direct and unambiguous one, widely used for the localised and simultaneous measurements of the above parameters. In Thomson scattering experiment, the light scattered by the plasma electrons is used for the measurements. The plasma electron temperature is measured from the Doppler shifted scattered spectrum and density from the total scattered intensity. A single point Thomson scattering system involving a Q-switched ruby laser and PMTs as the detector is deployed in ADITYA tokamak to give the plasma electron parameters. The system is capable of providing the parameters T e from 30 eV to 1 keV and n e from 5 × 1012cm−3−5 × 1013cm−3. The system is also able to give the parameter profile from the plasma center (Z=0 cm) to a vertical position of Z=+22 cm to Z=−14 cm, with a spatial resolution of 1 cm on shot to shot basis. This paper discusses the initial measurements of the plasma temperature from ADITYA.  相似文献   
98.
In this communication, a simple and straightforward procedure for the heterocyclization of 1H‐4,5‐dihydro‐3‐(4‐haloaryl)‐5‐substituted phenylpyrazoles (4) with 1‐bromo‐3‐chloropropane and 2,3‐dibromo‐1‐(4‐fluoro‐3‐methylphenyl)‐3‐phe‐ nylpropanone affording 2,3,4,8,9‐pentahydro‐7‐(4‐haloaryl)pyrazolo[5,1‐e]benzo[1,5] oxazocines 5 and regioselective synthesis of 2,3(erythro),7,8‐tetrahydro‐2‐ aryl‐3‐(4‐fluoro‐3‐methylbenzoyl)‐6‐(4‐halophenyl)pyrazolo[5,1‐d]benzo[1,4]oxa‐ zepines 6, respectively, via solid–liquid PTC is reported. All the synthesized compounds have been characterized on the basis of their spectral studies (IR, PMR, and MS) and analytical data.  相似文献   
99.
100.
Electrochemical methods for pollution abatement have been shown to be viable alternatives or complementary to biological treatment in some instances, especially when pollutants are recalcitrant to biological processing. Electrochemical oxidation and reduction have been found successful in decomposing the most resilient compounds, and electrolysis is assigned an important role in the elucidation of the electrode process. Small well-defined cathodic and anodic peak were observed that on controlled-potential electrolysis (CPE) reduced substantially with a considerable decrease in color and absorbance. The rate of decrease of the current and absorbance was found to exhibit a first-order dependence. The COD of the solutions showed a decrease from 1416 to 352 mg/L. No peak could be observed in the voltammograms after CPE, indicating the absence of any electroactive substance left in the solutions. Results show that electrochemical reduction is a superior technology for treatment of dyes, as there is no simultaneous addition of anions, such as sulfate or chloride.  相似文献   
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