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31.
Ion-exchangers are found not only in water purification processes, the original major application, but also in analytical chemistry for the separation and isolation of elements, hydrometallurgy, inorganic chemistry and biochemistry, in food technology, and of course in many specialized fields related to the utilization of atomic energy. The use of organic ion-exchangers is limited by virtue of their limited stability under harsh conditions, whereas inorganic ion-exchangers possess important properties, which make them very useful for chemical separation and purification in intense radiation fields. The availability of short-lived radionuclides from radionuclide generators provides an inexpensive and convenient alternative to in-house radioisotope production facilities such as accelerators and cyclotrons. Due to their simplicity of operation, chromatographic based generators have been the method of choice, although generators based on solvent extraction and on volatization and sublimation have also been developed, and are routinely used. In this paper use of inorganic ion-exchangers for the development of radionuclide generators for the decade 1993–2002 has been compiled.  相似文献   
32.
Bovine milk is an important food component in the human diet due to its nutrient-rich metabolites. However, bovine subclinical mastitis alters the composition and quality of milk. In present study, California mastitis testing, somatic cell count, pH, and electrical conductivity were used as confirmatory tests to detect subclinical mastitis. The primary goal was to study metabolome and identify major pathogens in cows with subclinical mastitis. In this study, 29 metabolites were detected in milk using gas chromatography–mass spectrometry. Volatile acidic compounds, such as hexanoic acid, hexadecanoic acid, lauric acid, octanoic acid, n-decanoic acid, tricosanoic acid, tetradecanoic acid, and hypogeic acid were found in milk samples, and these impart good flavor to the milk. Metaboanalyst tool was used for metabolic pathway analysis and principal component estimation. In this study, EC and pH values in milk were significantly increased (p < 0.0001), whereas fat (p < 0.04) and protein (p < 0.0002) significantly decreased in animals with subclinical mastitis in comparison to healthy animals. Staphylococcus aureus was the predominant pathogen found (n = 54), followed by Escherichia coli (n = 30). Furthermore, antibiotic sensitivity revealed that Staphylococcus aureus was more sensitive to gentamicin (79.6%), whereas Escherichia coli showed more sensitivity to doxycycline hydrochloride (80%).  相似文献   
33.
Current SDSL-EPR methods allow measurement of dipolar distances in the 8-70 A range; however, the use of extrinsic probes complicates the interpretation of these distances in modeling macromolecular structure and conformational changes. The data presented here show that interprobe distances correlate only weakly with Cbeta-Cbeta distances, especially for distances that are on the order of the spin label tether lengths. Explicitly incorporating the spin label into the modeling process increases the experiment/model correlation 4-fold and reduces the distance error from 6 A to 3 A.  相似文献   
34.
Physics of Atomic Nuclei - The even—even rare-earth nuclei in U(5)—SU(3) region at neutron number (N) = 90, have been systematically studied using the Bohr—Mottelson Model (BM),...  相似文献   
35.
Acta Mathematica Sinica, English Series - In this research article, we shall give some reverse Arithmetic-Geometric mean inequalities for unital positive linear maps on Hilbert space operators...  相似文献   
36.
37.
The linear properties of magnetosonic waves are studied in nearly degenerate and nearly non-degenerate quantum plasmas composed of electrons, positrons and ions in the presence of spin- effect. Using the fluid equations, a generalized dispersion relation for perpendicular and oblique propagation is derived. It is found that degree of temperature and spin degeneracy modify the dispersive properties of the given modes. The results of analysis are beneficial for understanding the collective phenomena in dense quantum astrophysical plasmas.  相似文献   
38.
Bone seeking radiopharmaceuticals such as ethylenediaminetetramethylene phosphonate (EDTMP) complexes of 153Sm and 166Ho are receiving considerable attention for therapeutic treatment of bone metastases. Rhenium-188 has both beta-particle emissions for a therapeutic effect and gamma-emissions for imaging and it is available from an in-house generator system similar to the current 99mTc generator, which makes it convenient for clinical use. The preparation of 188Re-EDTMP is described using 188Re, which was obtained from the alumina-based 188W/188Re generator. Dependence of the radiolabeling yield of 188Re-EDTMP on reducing agent concentration, EDTMP concentration, incubation time, pH and addition of carrier was examined. In the case of optimum conditions, the radiolabeling yields of 188Re-EDTMP were ~98% for carrier-free as well as carrier-added 188Re. The addition of ascorbic acid plays an important role in the stability of carrier-free as well as carrier-added 188Re-EDTMP preparations. The biodistribution of carrier-free and carrier-added 188Re-EDTMP compounds in rats was also studied. The results show that 188Re (carrier-added)-EDTMP is a potential bone pain palliation radiopharmaceutical due to its high skeletal uptake, rapid blood clearance and relatively low soft tissue absorption.  相似文献   
39.
Structural and spectroscopic data on the series of compounds “PhSeX”, where X = Cl, CN or SCN, are reported and compared with previously reported data on “PhSeX” systems (X = Br and I). The chloro-compound displays a “square” motif, Ph4Se4Cl4, in the solid state, linked by long Se–Se bonds [2.993(3)–3.035(3) Å], and forms a loosely held network of Se4 and Cl4 squares in its extended structure. In contrast, the pseudohalogen derivatives, PhSeCN and PhSeSCN, consist of essentially monomeric units, which form chains held together by weak Se?N interactions in the solid state. These Se?N interactions are much shorter in PhSeCN, 3.023(3)–3.065(4) Å, than in PhSeSCN, 3.348(4) Å. Weaker Se?N contacts are also present between the chains. The structure of PhSeSCN described here is the first reported crystallographic study of a selenium thiocyanate compound. Spectroscopic studies suggest that all three compounds exist as monomers in solution. The results reported herein illustrate the subtle differences in the solid-state structures of PhSeX compounds.  相似文献   
40.
Production of hydrogen (H2) and oxygen (O2) through electrocatalytic water splitting is one of the sustainable,green and pivotal ways to accomplish the ever-inc...  相似文献   
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