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11.
A new four‐way multiblock method is proposed to study the links between more than two sets of data tables (several multiblocks) measured on the same observations. This method, called STATIS‐4, generalizes the STATIS method to more than one set of matrices. In its first step, STATIS‐4 is searching for one consensus for each multiblock and a global consensus summarizing all the previous ones as good as possible. Some graphical representations can be made to visualize the proximities between the tables within a multiblock and to visualize those between all the multiblocks. Moreover, plots of the observations for each table, each multiblock and global observations can be made. The theory of STATIS‐4 and the algorithm used to obtain the optimal solutions are presented. Moreover, a real sensory dataset is studied with STATIS‐4. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
12.
Litsea glutinosa (L. glutinosa) is considered an evidence-based medicinal plant for the treatment of cancer, the leading cause of death worldwide. In our study, the in vitro antioxidant and in vivo anticancer properties of an essential ethno-medicinal plant, L. glutinosa, were examined using non-toxic doses and a phytochemical analysis was executed using gas-chromatography–mass-spectrometry. The in vitro antioxidant study of the L. glutinosa methanolic extract (LGBME) revealed a concentration-dependent antioxidant property. The bark extract showed promising antioxidant effects in the 2,2-diphenyl-1-picryl-hydrazyl (DPPH) assay. The strongest antioxidant activity was demonstrated at the maximum concentration (50 µg/mL). The IC50 values of the LGBME and BHT were 5.51 and 5.01 µg/mL, respectively. At the same concentration, the total antioxidant capacity of the LGBME was 0.161 µg/mL and the ferric reducing antioxidant power assay result of the LGBME was 1.783 µg/mL. In the cytotoxicity study, the LD50 of the LGBME and gallic acid were 24.93 µg/mL and 7.23 µg/mL, respectively. In the in vivo anticancer-activity studies, the LGBME, particularly at a dose of 150 mg/kg/bw, showed significant cell-growth inhibition, decreased tumor weight, increased mean survival rate, and upregulated the reduced hematological parameters in EAC (Ehrlich’s ascites carcinoma)-induced Swiss albino mice. The highest cell-growth inhibition, 85.76%, was observed with the dose of 150 mg/kg/bw. Furthermore, the upregulation of pro-apoptotic genes (p53, Bax) and the downregulation of anti-apoptotic Bcl-2 were observed. In conclusion, LGBME extract has several bioactive phytoconstituents, which confirms the antioxidant and anticancer properties of L. glutinosa.  相似文献   
13.
Modal behavior in landmines has recently become a topic of interest for acoustic landmine detection. It is well known that landmines exhibit mechanical resonance behavior that enhances the soil velocity over a buried landmine. Recent experimental work by Zagrai et al. [A. Zagrai, D. Donskoy, and A. Ekimov, J. Acoust. Soc. Am. 118 (6), 3619-3628 (2005)] demonstrates the existence of structural modes in several landmines. The work reported herein parallels the work of Zagrai et al. in studying the structural modes of the pressure plate of a plastic, cylindrically symmetric, antitank landmine. The pressure plate is considered to act as an elastically supported thin elastic plate. An observed perturbation of the first symmetric mode of the pressure plate is caused by the landmine's shock-resisting mechanism. This is validated by a lumped element model for the first symmetric mode coupled to the shock-resisting mechanism.  相似文献   
14.
Human footsteps generate broadband frequency vibrations in the ground/floor and sound in the air from a few Hertz up to ultrasonic frequencies due to striking and sliding contacts between a foot and the ground/floor. The high-frequency (above 1 kHz) vibrations from footsteps were detected on a building floor, but were not detected on the outdoor ground, even at 1 m from a walker. This paper presents results of ultrasound registration from footsteps on the ground at greater distances. Results are based on sound measurements in air, since the sound absorption in air is less than vibration absorption in the ground.  相似文献   
15.
Synthesis of two protected peptides thirteen and fourteen residues long, sequence 5-17, i.e. Fmoc-Tyr(cHex)- Ile-Val-Asp(Bzl)-Asp(Bzl)-Val-Asn-Cys(Acm)-Thr(Bzl)-Tyr(cHex)- Phe-Cys(Acm)-Gly-OH, and 18-31, i.e. Fmoc-Arg (Tos)-Asn-Ala- Tyr(cHex)-Cys(Acm )-Asn-Glu(Bzl)-Glu(Bzl)-Cys(Acm)-Thr(Bzl)- Lys(Z)-Leu-Lys(Z)-Gly-OH, of the scorpion neurotoxin II from , was performed by the solid phase method. The hydroxymethylphenoxymethyl copoly(styrene - 1% -divinylbenzene) type resin was used in combination with Fmoc-amino acids for both syntheses. A general protocol minimizing side reactions has been developed for the use of the base labile Fmoc--amino protecting group. The time of reaction with piperidine (50% in N,N'-dimethylformamide) has been shortened to three times one minute and coupling was performed mainly in methylene chloride with just dicyclohexyl or diisopropyl-carbodiimide. The side chain protecting groups of the Fmoc--amino acids were of the hydrogen fluoride labile type, which permitted, after trifluoroacetic acid cleavage of the peptide to resin ester bond, obtainment of protected peptides. The crude segments, precipitated from N,N'-dime- thylacetamide with water, were highly purified by HPLC and chemically characterized for future use in convergent solid phase assembling.  相似文献   
16.
17.
The evaluation of surface roughness in agricultural settings is investigated. Previous work has shown that sound propagating in a direction parallel to a smooth porous ground attenuates more rapidly than in a free space. This attenuation is due to absorption of the sound in the air filled pores in the ground. Previous work has also shown that a comparable attenuation phenomenon exists for propagation over a rough surface, albeit from different attenuation mechanisms. It is proposed that these additional attenuation mechanisms can be used to quantify the surface roughness, even on a porous surface. Attempts to model observed data with an effective impedance or reflection coefficient, in order to quantify the surface roughness, have had some success but have met with some problems for certain propagation geometries and surface configurations. Experimental data and modeling results will be presented and discussed for a variety of surfaces ranging in surface properties from impermeable to loosely packed soil and ranging in surface roughness scales from low sloped perturbations to steeply sloped wedges.  相似文献   
18.
We give a method of constructing nonlinear Schrödinger equations which are similar to the Davey-Stewartson equation, but in N+1 dimensions, and posses, by construction, solutions describing interacting soliton-like objects.  相似文献   
19.
Measurements of the top surface vibration of a buried (inert) VS 2.2 anti-tank plastic landmine reveal significant resonances in the frequency range between 80 and 650 Hz. Resonances from measurements of the normal component of the acoustically induced soil surface particle velocity (due to sufficient acoustic-to-seismic coupling) have been used in detection schemes. Since the interface between the top plate and the soil responds nonlinearly to pressure fluctuations, characteristics of landmines, the soil, and the interface are rich in nonlinear physics and allow for a method of buried landmine detection not previously exploited. Tuning curve experiments (revealing "softening" and a back-bone curve linear in particle velocity amplitude versus frequency) help characterize the nonlinear resonant behavior of the soil-landmine oscillator. The results appear to exhibit the characteristics of nonlinear mesoscopic elastic behavior, which is explored. When two primary waves f1 and f2 drive the soil over the mine near resonance, a rich spectrum of nonlinearly generated tones is measured with a geophone on the surface over the buried landmine in agreement with Donskoy [SPIE Proc. 3392, 221-217 (1998); 3710, 239-246 (1999)]. In profiling, particular nonlinear tonals can improve the contrast ratio compared to using either primary tone in the spectrum.  相似文献   
20.
Scorpion venom is a rich source of promising therapeutic compounds, such as highly selective ion channel ligands with potent pharmacological effects. Bot33 is a new short polypeptide of 38 amino acid residues with six cysteines purified from the venom of the Buthus occitanus tunetanus scorpion. Bot33 has revealed less than 40% identity with other known alpha-KTx families. This peptide displayed a neutral amino acid (Leucine), in the position equivalent to lysine 27, described as essential for the interaction with Kv channels. Bot33 did not show any toxicity following i.c.v. injection until 2 µg/kg mouse body weight. Due to its very low venom concentration (0.24%), Bot33 was chemically synthesized. Unexpectedly, this peptide has been subjected to a screening on ion channels expressed in Xenopus laevis oocytes, and it was found that Bot33 has no effect on seven Kv channel subtypes. Interestingly, an in silico molecular docking study shows that the Leu27 prevents the interaction of Bot33 with the Kv1.3 channel. All our results indicate that Bot33 may have a different mode of action from other scorpion toxins, which will be interesting to elucidate.  相似文献   
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