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81.
This article presents the investigation on the large-scale synthesis of ZnO microrods with a simple low temperature hydrothermal method without using surfactants, organic solvents, or catalytic reagents. The synthesized ZnO powder is characterized with different techniques. The X-ray diffraction study reveals the excellent crystal quality of the ZnO product possessing the hexagonal (wurtzite-type) crystal structure. The scanning electron microscope observation confirms the formation of six faceted prismatic hexagonal ZnO microrods with the aspect ratio of 10. It also reveals that the ZnO microrods grow along the (0 0 0 1) direction and finally emerge with a sharp tip because of the existence of polar faces. The UV–vis spectrum shows a sharp absorption peak centered at 370 nm, which is in a good agreement with the equivalent bulk band gap value. The strong UV absorption peak implies the excellent crystal quality of the synthesized ZnO microrods. Room temperature photoluminescence spectroscopic study of the ZnO microrods with different excitation wavelengths reveals a strong band edge emission peak centered at 398 nm and a defect related visible blue emission peak at 460 nm. The decrease in photoluminescence intensity with negligible red shift in peak position is observed with increasing excitation wavelength. 相似文献
82.
83.
Kale Amol Bandela Narsingrao Kulkarni Jeetendra 《Journal of Radioanalytical and Nuclear Chemistry》2020,323(1):151-157
The main objective of study is assessment of chemo-radiological risk using measured concentrations of uranium in drinking water. For estimation of U concentration, LED Fluorimeter was used. For data accuracy, statistical tools were applied, geographical distribution GIS based software were used. To assess relation between uranium to other parameters, correlation test was performed. On the basis of presence of U in the water, hazard quotient, effective dose and cumulative dose for lifetime were estimated, it ranges from 0.001 to 1.09, 0.01–18.61 μSv year−1 and 1.22–1303 μSv for lifetime correspondingly. The estimated ingested dose is well below than the suggested limit of 0.1 mSv.
相似文献84.
Polyethylene glycol derivatives, such as block copolymers of polyethylene glycol and diacyllipids (for example, phosphatidylethanolamine)
are widely used for surface modification of various pharmaceutical carriers in order to impart them longevity in the body.
To make polyethylene glycol detachable from the surface of pharmaceutical carrier and facilitate the interaction of the carrier
with target cells when in pathological zone, we have prepared a set of polyethylene glycol-phosphatidylethanolamine block
copolymers with the pH sensitive hydrazone bond between polyethylene glycol and phosphatidylethanolamine, which destabilizes
at lowered pH values typical for tumors and inflammation zones. We have demonstrated that the stability of the hydrazone bond
at normal physiological pH (7.4) as well as the rate of its hydrolysis at pH 6 and below strongly depend on the type of substitutions
at this bond. Using aliphatic and aromatic aldehydes and ketones, polyethylene glycol-phosphatidylethanolamine block copolymers
were prepared with different stabilities and degradation rates, which can be useful in constructing stimuli-sensitive pharmaceutical
carriers.
The text was sabmitted by the authors in English.
This work was supported by the NIH grants RO1 HL55519 and RO1 CA121838 to V.P. Torchilin. 相似文献
85.
Cd0.5Zn0.5Se composite thin films were obtained on glass substrate using aqueous alkaline solution at low temperature using cadmium acetate and zinc acetate as Cd2+ and Zn2+ and Se2− ion sources. Different phases of individuals i.e. CdSe and ZnSe, spherical and needle shape surface morphology and good elemental chemical stoichiometric ratio were observed from X-ray diffraction, scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX) studies, respectively. The band gap and electrical resistivity of the composite film were 2.35 eV and about 107 Ω cm, respectively. 相似文献
86.
Neville F Gidalevitz D Kale G Nelson A 《Bioelectrochemistry (Amsterdam, Netherlands)》2007,70(2):205-213
LL-37 is an alpha-helical antimicrobial peptide of human origin. It is a 37 residue cathelicidin peptide. This paper explores the use of electrochemical methods to investigate the interaction of LL-37 with phospholipid and lipid A monolayers on a mercury drop electrode. Experiments were carried out in Dulbecco's phosphate buffered saline at pH approximately 7.6. The capacity-potential curves of the coated electrode in the presence and absence of LL-37 were measured using out-of-phase ac voltammetry. The frequency dependence of the complex impedance of the coated electrode in the presence and absence of LL-37 was estimated at -0.4 V versus Ag/AgCl 3.5 mol dm(-3) KCl. The monolayer permeability to ions was studied by following the reduction of Tl(I) to Tl(Hg) at the coated electrode. LL-37 shows no significant interaction with DOPC. However, LL-37 shows a small interaction with DOPG and lipid A within a DOPC monolayer where the monolayer permeability is marginally increased and the zero frequency capacitance (ZFC) is marginally decreased in both cases. LL-37 shows a significant interaction with a lipid A monolayer thereby decreasing the ZFC by 30%. The results concur with the known membrane active properties of LL-37 and establish this electrochemical approach as a key technique for screening peptides. 相似文献
87.
88.
Ubale S. B. Kale S. B. Mane V. J. Bagwade P. P. Lokhande C. D. 《Journal of Solid State Electrochemistry》2021,25(6):1753-1764
Journal of Solid State Electrochemistry - A simple and inexpensive successive ionic layer adsorption and reaction (SILAR) method was used for synthesis of ytterbium sulfide (Yb2S3) thin film. The... 相似文献
89.
Ch. N. Rao S. Shanmukharao Samatham V. Ganesan V.G. Sathe D.M. Phase S.N. Kale 《Journal of magnetism and magnetic materials》2012
The perovskite manganite systems have been the materials of tremendous interest due to their strong correlation between structure, transport and magnetism. These materials in their single-crystal form show colossal magneto-resistance (CMR), but the applied fields are very high (∼1–5 T). The polycrystalline samples do show high low-field magneto-resistance (LFMR), but good amount of control over particle sizes and grain-boundary distribution is required, which is well known but less realized in practical approaches. In this context, we report on synthesis and manipulation of polycrystalline La0.7Ba0.3MnO3 (LBMO) submicron powders using citric acid chelation. The Citrate-gel route is used to synthesize poly-dispersed LBMO powders which are subjected to citrate chelation for a duration of 0 (LB0) to 4 h(LB4) . The samples show improved ordering in X-ray diffraction patterns. Raman spectroscopy scans indicate changed mode signatures due to the probable chelating process, which alters the surface morphology. X-ray photoelectron microscopy shows an evidence of fine citrate layer on the grain boundaries. Low temperature B–H curves exhibit fine hysteresis loops for all samples, while room temperature B–H curves shows paramagnetic response. Scanning electron microscopy images showed the formation of well arranged, connected, mono-dispersed grains of LB4 sample, as against polydispered LB0. The magneto-resistance (at H=100 kOe) is seen to enhance for LB4 at its transition temperature (75%, as compared to LB0, where it is 60%), which can be attributed to the well-controlled inter-grain tunneling phenomenon and thin insulating regions in between, created due to citrate chelation, which probably enhances the scattering phenomenon and its susceptibility to applied fields. As citric acid is known to chelate Mn ions, it probably chelates the smaller LB particulate structure and leaves behind citrate-connected submicron grains of LBMO, which are seen to be well engineered. 相似文献
90.
Beldar Vishal Gokul Kale Balasaheb Shantilal Pagare Ravikiran Jadhao Manojkumar 《Chemistry of Natural Compounds》2022,58(4):754-756
Chemistry of Natural Compounds - 相似文献