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151.
We study effects of noncommutativity on the phase space generated by a non-minimal scalar field which is conformally coupled to the background curvature in an isotropic and homogeneous FRW cosmology. These effects are considered in two cases, when the potential of scalar field has zero and nonzero constant values. The investigation is carried out by means of a comparative detailed analysis of mathematical features of the evolution of universe and the most probable universe wave functions in classically commutative and noncommutative frames and quantum counterparts. The influence of noncommutativity is explored by the two noncommutative parameters of space and momentum sectors with a relative focus on the role of the noncommutative parameter of momentum sector. The solutions are presented with some of their numerical diagrams, in the commutative and noncommutative scenarios, and their properties are compared. We find that impose of noncommutativity in the momentum sector causes more ability in tuning time solutions of variables in classical level, and has more probable states of universe in quantum level. We also demonstrate that special solutions in classical and allowed wave functions in quantum models impose bounds on the values of noncommutative parameters.  相似文献   
152.
153.
    
The structural stabilities and electronic properties of C20 fullerene and some its incorporated boron and nitrogen derivatives are probed at B3LYP/AUG‐cc‐pVTZ level of theory. According to density functional theory results, the topology of inserted B or N heteroatoms in [20]‐fullerene perturbs strongly the stability, energy, geometry, charge, polarity, nucleus‐independent chemical shifts, aromaticity, and highest‐occupied molecular orbital and lowest‐unoccupied molecular orbital (HOMO–LUMO) gap of the resulting heterofullerenes. Vibrational frequency (υmin) calculations show that except N10C10, all other BbNnC20‐(b + n) heterofullerenes with b, and n = 0, 4, 5, 8, and 10 are true minima. The calculated band gaps (∆EHOMO–LUMO) of B8C12, and N8C12 (2.86 eV), show them the most stable heterofullerenes against electronic excitations. While 10 B substituting in equatorial position increase the conductivity of B10C10 through decreasing its band gaps, 10 N doping in equatorial position enhance stability of N10C10 against electronic excitations via increasing its band gaps. High natural bond orbital and Mulliken charge transfer on the surfaces of B atoms, especially B5N5C10with five B–N bonds in the equatorial position, provokes further investigation on its possible application for hydrogen storage. Nucleus‐independent chemical shift values show that B5N5C10 is the most aromatic species. The calculated heat of atomization per carbon (ΔHat/C) of B8C12 shows it the most thermodynamic stable heterofullerenes of each. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
154.
    
Phosphotungstic acid (H3PW12O40, PTA) supported on ZIF‐9(NH2) was synthesized for the first time and performed as an effective and environmental friendly catalyst in the one‐pot three component Biginelli condensation of different substituted benzaldehydes with ethyl acetoacetate and urea to afford the corresponding 3,4‐dihydropyrimidin‐2‐(1H)‐ones under solvent‐free conditions. ZIF‐9(NH2) and the prepared nanocatalyst PTA@ZIF‐9(NH2) were characterized by XRD, FESEM, TEM, EDX, BET, AAS, TGA, UV–Vis, and FT‐IR. After reaction, the nanocatalyst can be easily separated from the reaction mixture by centrifuge and the recovered catalyst can be reused for at least five times with a 14% reduction in yield after the fifth run. This study showed that ZIF‐9(NH2) can be utilized as a promising support for PTA and developed a highly active, stable and reusable heterogeneous catalyst under easy reaction condition in the multi‐component organic synthesis.  相似文献   
155.
We studied a rapid, sensitive and selective amperometric sensor for determination of hydrogen peroxide by electrodeposited Ag NPs on a modified glassy carbon electrode (GCE). The modified GCE was constructed through a step by step modification of magnetic chitosan functional composite (Fe3O4–CH) and high-dispersed silver nanoparticles on the surface. The resulted Ag@Fe3O4–CH was characterized by various analytical methods including Fourier transform infrared spectroscopy, X-ray diffraction, transmission electron microscopy, scanning electron microscopy and cyclic voltammetry. The proposed sensor employed Ag@Fe3O4–CH/GCE as the working electrode with a linear current response to the hydrogen peroxide concentration in a wide range from 0.01 to 400 µM with a low limit of detection (LOD = 0.0038 µM, S/N = 3). The proposed sensor showed superior reproductivity, sensitivity and selectivity for the detection of hydrogen peroxide in environmental and clinical samples.  相似文献   
156.
Although structural isomers may yield indistinguishable ion mobility (IM) arrival times and similar fragment ions in tandem mass spectrometry (MS), it is demonstrated that post-IM/collision-induced dissociation MS (post-IM/CID MS) combined with chemometrics can enable independent study of the IM-overlapped isomers. The new approach allowed us to investigate the propensity of selected b type fragment ions from AlaAlaAlaHisAlaAlaAla-NH2 (AAA(His)AAA) heptapeptide to form different isomers. Principle component analysis (PCA) of the unresolved post-IM/CID profiles indicated the presence of two different isomer types for b4 +, b5 +, and b6 + and a single isomer type for b7 + fragments of AAA(His)AAA. We employed a simple-to-use interactive self-modeling mixture analysis (SIMPLISMA) to calculate the total IM profiles and CID mass spectra of b fragment isomers. The deconvoluted CID mass spectra showed discernible fragmentation patterns for the two isomers of b4 +, b5 +, and b6 + fragments. Under our experimental conditions, calculated percentages of the “cyclic” isomers (at the 95 % confidence level for n = 3) for b4 +, b5 +, and b6 + were 61 (± 5) %, 36 (± 5) %, and 48 (± 2) %, respectively. Results from the SIMPLISMA deconvolution of b5 + species resembled the CID MS patterns of fully resolved IM profiles for the two b5 + isomers. The “cyclic” isomers for each of the two-component b fragment ions were less susceptible to ion fragmentation than their “linear” counterparts.
?  相似文献   
157.
Breast cancer radioimmunoscintigraphy targeting HER2/neu expression is a growing field of work in nuclear medicine research. Trastuzumab is a monoclonal antibody that binds with high affinity to HER2/neu, which is over expressed on breast and other tumors. Developing new tracers for the detection of this cancer is of great interest. In this study, trastuzumab was successively labeled with [64Cu]CuCl2 after conjugation with DOTA-NHS-ester. The conjugate was purified by molecular filtration, the average number of DOTA conjugated per mAb was calculated and total concentration was determined by spectrophotometric method. DOTA–trastuzumab was labeled with 64Cu produced by 68Zn(p,αn)64Cu nuclear reaction (30 MeV protons at 180 μA). Radiochemical purity, integrity of protein after radiolabeling and immunoreactivity of radiolabeled mAb trastuzumab with HER2/neu antigen and SkBr3 cell line were performed by RIA. In vitro stability of radiolabeled mAb in human serum was determined by thin layer chromatography. In vitro internalization studies were performed with the SkBr3 cell line and the tissue biodistribution of the 64Cu–DOTA–trastuzumab was evaluated in wild-type rat (90 ± 5.5 μCi, 2, 6, 12, 24 h p.i.). The radioimmunoconjugate was prepared with a radiochemical purity of higher than 96 ± 0.5 % (ITLC) and specific activity as high as 5.3 μCi/μg. The average number of chelators per antibody for the conjugate used in this study was 5.8/1. The sample was showed to have similar patterns of migration in the gel electrophoresis. The 64Cu–DOTA–trastuzumab showed high immunoreactivity towards HER2/neu antigen and SkBr3 cell line. In vitro stability of the labeled product was found to be more than 94 % in PBS and 82 ± 0.5 % in human serum over 48 h. In vitro internalization studies of the 64Cu–DOTA–trastuzumab showed that up to 11.5 % of the radioimmunoconjugate internalized after 10 h. The accumulation of the radiolabeled mAb in liver, skin, intestine, lung, spleen, kidney and other tissues demonstrates a similar pattern to the other radiolabeled anti-HER2 immunoconjugates. 64Cu–DOTA–trastuzumab is a potential compound for molecular imaging of PET for diagnosis and treatment studies and follow-up of HER2 expression in oncology.  相似文献   
158.
Summary Let G be a finite group. Order components of G were introduced in Chen [5]. Let OC(G) be the set of order components of G. Some finite groups are characterizable by their order components. This assertion was proved for the simple groups PSU(p,q), where p=3, 5, 7 and 11. In this paper, we prove that the simple groups PSU(p,q) can be uniquely determined by their order components, where p≥13 is a prime number. Main consequences of our results are the validity of a conjecture of J. G. Thompson and another conjecture of W. Shi and J. Bi for the groups under consideration.  相似文献   
159.
    
In this project, the in-situ formation of magnetic nanoparticles modified with pectin and acetamide was presented and used as a sorbent in the magnetic solid-phase extraction method. The synthesis of the magnetic sorbent was studied by various characterization methods. The sorbent was employed for the microextraction of four model analytes including methyl paraben, ethyl paraben, propyl paraben, and butyl paraben. The separation and measurement of the extracted compounds were done by high-performance liquid chromatography-ultraviolet detection. In order to achieve the best extraction condition, factors affecting the extraction efficiency were investigated and optimized using response surface methodology. In the obtained optimized condition, the following parameters were achieved: limits of detection: 0.16–0.28 µg/L, limits of quantification: 0.49–0.92 µg/L, and intra- and inter-day relative standard deviations: 1.2%–6.6% and 1.6%–4.8%, respectively. The linear dynamic ranges of the method for methyl paraben, ethyl paraben, butyl paraben, and propyl paraben were 1–200, 0.5–500, 1–500, and 1–500 µg/L, respectively. In order to investigate the effectiveness of the method, the proposed magnetic nanosorbent was used to measure the desired parabens in cosmetic samples. The results showed good accuracy and precision of the developed method for the determination of trace amounts of target analytes.  相似文献   
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