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排序方式: 共有543条查询结果,搜索用时 15 毫秒
1.
Rathore Vikas Tiwari Budhi Sagar Nema Sudhir Kumar 《Plasma Chemistry and Plasma Processing》2022,42(1):109-129
Plasma Chemistry and Plasma Processing - The present study has been carried to investigate the interaction and effect of plasma activated water (PAW) on pea seeds. PAW is produced with the... 相似文献
2.
Trabecular bone fracture is closely related to the trabecular architecture, microdamage accumulation, and bone tissue properties. Primary constituents of trabecular tissue are hydroxyapatite (HA) mineralized type-I collagen fibers. In this research, dynamic fracture in two dimensional (2-D) micrographs of ovine (sheep) trabecular bone is modeled using the mesoscale cohesive finite element method (CFEM). The bone tissue fracture properties are obtained based on the atomistic strength analyses of a type-I collagen + HA interfacial arrangement using molecular dynamics (MD). Analyses show that the presented framework is capable of analyzing the architecture dependent fracture in 2-D micrographs of trabecular bone. 相似文献
3.
Excess enthalpies of mixing H
m
E
of tetrahydrofuran and tetrahydropyran with trichloromethane, tetrachloromethane, 1,2-dichloroethane, 1,1,2-trichloroethane and 1,1,2,2-tetrachloroethane have been determined at 26.9°C and are found to be negative over the entire composition range for both sets of the ether mixtures. H
m
E
decreases in the sequence; dichloroethane > tetrachloromethane > trichloroethane > trichloromethane > tetrachloroethane. The results are explained on the basis of strong O...H-C and weak Cl...O specific interactions. Flory's theory has been used to correlate the experimental data with good agreement found between the theoretical and experimental values of H
m
E
. 相似文献
4.
Why chaos is rarely observed in natural populations 总被引:2,自引:0,他引:2
An attempt has been made to understand why chaotic dynamics have received poor evidential support from field studies. Our study opens up the possibility that the cause of failure might not be poor quality of data, as pointed out by earlier authors, but an ecological reality. We have designed two model food chains to examine whether there is a biological basis for the crisis. This investigation is effected with the help of a new method which we introduce at an appropriate place in the text. The fact that chaos exists in a narrow range of parametric values in both the model systems suggests that the crisis indeed has a biological origin. 相似文献
5.
Josephson effects have been observed in bulk samples of Y-Ba-Cu-O. The magnitude of the zero-voltage current is found to change
systematically with externally applied small magnetic fields of a few mG. It is also found to vary when samples are irradiated
with microwaves. These observations suggest the presence of inter-grain Josephson junctions. 相似文献
6.
Vikas V. Vaidya Santosh M. Yetal Shikha M. N. Roy Noel A. Gomes Santosh S. Joshi 《Chromatographia》2007,66(11-12):925-928
A rapid, sensitive and specific method to quantify pregabalin in human plasma using metaxalone as the internal standard is described. Sample preparation involved simple protein precipitation by using acetronitrile as solvent. The extract was analyzed by high-performance liquid chromatography coupled to electrospray tandem mass spectrometry (LC-MS–MS). Chromatography was performed isocratically on Thermo Hypurity C18 5 μm analytical column, (50 mm × 4.6 mm i.d.). The assay of pegabalin was linear calibration curve over the range 10.000–10000.000 ng mL?1. The lower limit of quantification was 10.000 ng mL?1 in plasma. The method was successfully applied to the bioequivalence study of pregabalin capsules (150.0 mg) administered as a single oral dose. 相似文献
7.
R. S. Tomar Prakash Bhartia 《International Journal of Infrared and Millimeter Waves》1986,7(9):1281-1295
New design data for an open suspended microstripline is reported. Two most commonly used substrate materials, namely RT-Duroid (r=2.22) and fused quartz (r=3.78) are considered. Effects of dispersion and strip thickness are included in the results which are based on a fullwave spectral-domain analysis. The data, which is computed over the complete practical ranges of frequency and parameter values, is much more reliable than the currently available quasistatic results. 相似文献
8.
Nanda V Rosenblatt MM Osyczka A Kono H Getahun Z Dutton PL Saven JG Degrado WF 《Journal of the American Chemical Society》2005,127(16):5804-5805
Metal-binding sites in metalloproteins frequently occur at the interfaces of elements of secondary structure, which has enabled the retrostructural analysis of natural proteins and the de novo design of helical bundles that bind metal ion cofactors. However, the design of metalloproteins containing beta-structure is less well developed, despite the frequent occurrence of beta-conformations in natural metalloproteins. Here, we describe the design and construction of a beta-protein, RM1, that forms a stable, redox-active 4-Cys thiolate Fe(II/III) site analogous to the active site of rubredoxin. The protein folds into a beta-structure in the presence and absence of metal ions and binds Fe(II/III) to form a redox-active site that is stable to repeated cycles of oxidation and reduction, even in an aerobic environment. 相似文献
9.
Tucker MJ Getahun Z Nanda V DeGrado WF Gai F 《Journal of the American Chemical Society》2004,126(16):5078-5079
We studied here the binding of the mastoparan X peptide to a zwitterionic lipid bilayer (POPC) and demonstrated that nitrile-derivatized amino acids can be used to determine the hydration state (or change in hydration state) of specific sites of membrane-interactive peptides (upon binding). We have also shown that polarized ATR-FTIR measurements can further be used to uncover information regarding the spatial orientation of individual side chains as well as their conformational preference within the lipid bilayer. 相似文献
10.