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991.
Oxidized regenerated cellulose (ORC) has been used as an absorbable hemostat since World War II. In the present study, hemostasis time was determined in a spleen incision model in swine. The effect of mass on absorbable hemostat efficacy and hemostasis time was evaluated by standardizing the ORC materials on a mass basis. The median hemostasis time for a single layer of the new nonwoven ORC was as much as 51 % shorter than woven ORC (P < 0.001). The mean hemostasis time for nonwoven ORC was not affected by the mass of hemostat applied to the wound. The hemostatic efficacy of woven ORC increased with the mass (layers) of hemostat applied to the wound. Nonwoven ORC is significantly faster in achieving hemostasis than woven ORC, and its hemostatic efficacy is not influenced by the mass of material applied. Tissue reaction was minimal and the material was fully absorbed by 14 days.  相似文献   
992.
993.
New methallylsilanated phosphorylcholine (MASPCs) were synthesized via a copper-catalyzed ‘click’ reaction and demonstrated excellent moisture stability. Hydroxylated silicon compounds, silanol, and silica were grafted or modified by MASPCs in the presence of triflic acid (TfOH) and they possessed a good grafting efficiency and high loading rate.  相似文献   
994.
A highly environmentally benign protocol for the synthesis of quinazolinones from anthranilamides and aldehydes via aerobic oxidation was developed in wet DMSO. This protocol is operationally simple, exhibits broad substrate scope, and does not need toxic metal catalysts and bases. In addition, the utility of this transformation was further demonstrated by converting the resulting quinazolinones into other useful products in the same-pot without their isolation.  相似文献   
995.
Oral fluid (OF) enables non-invasive sample collection for on-site drug testing, but performance of on-site tests with occasional and frequent smokers’ OF to identify cannabinoid intake requires further evaluation. Furthermore, as far as we are aware, no studies have evaluated differences between cannabinoid disposition among OF collection devices with authentic OF samples after controlled cannabis administration. Fourteen frequent (≥4 times per week) and 10 occasional (less than twice a week) adult cannabis smokers smoked one 6.8 % ?9-tetrahydrocannabinol (THC) cigarette ad libitum over 10 min. OF was collected with the StatSure Saliva Sampler, Oral-Eze, and Draeger DrugTest 5000 test cassette before and up to 30 h after cannabis smoking. Test cassettes were analyzed within 15 min and gas chromatography–mass spectrometry cannabinoid results were obtained within 24 h. Cannabinoid concentrations with the StatSure and Oral-Eze devices were compared and times of last cannabinoid detection (t last) and DrugTest 5000 test performance were assessed for different cannabinoid cutoffs. 11-nor-9-Carboxy-THC (THCCOOH) and cannabinol concentrations were significantly higher in Oral-Eze samples than in Stat-Sure samples. DrugTest 5000 t last for a positive cannabinoid test were median (range) 12 h (4–24 h) and 21 h (1–?≥?30 h) for occasional and frequent smokers, respectively. Detection windows in screening and confirmatory tests were usually shorter for occasional than for frequent smokers, especially when including THCCOOH ≥20 ng L?1 in confirmation criteria. No differences in t last were observed between collection devices, except for THC ≥2 μg L?1. We thus report significantly different THCCOOH and cannabinol, but not THC, concentrations between OF collection devices, which may affect OF data interpretation. The DrugTest 5000 on-site device had high diagnostic sensitivity, specificity, and efficiency for cannabinoids.  相似文献   
996.
Khinchin's theorem of ergodicity is examined by means of linear response theory. The resulting ergodic condition shows that, contrary to the theorem, irreversibility is not a sufficient condition for ergodicity. By the recurrence relations method, we prove that irreversibility is broader in scope than ergodicity, showing why it can only be a necessary condition for ergodicity.  相似文献   
997.
We present studies of the photoexcited quasiparticle dynamics in Tl(2)Ba(2)Ca(2)Cu(3)O(y) (Tl-2223) using femtosecond optical techniques. Deep into the superconducting state (below 40 K), a dramatic change occurs in the temporal dynamics associated with photoexcited quasiparticles rejoining the condensate. This is suggestive of entry into a coexistence phase which, as our analysis reveals, opens a gap in the density of states (in addition to the superconducting gap), and furthermore, competes with superconductivity resulting in a depression of the superconducting gap.  相似文献   
998.
Through Haldane's construction, the fractional quantum Hall states on a two-sphere were shown to be the ground states of one-dimensional SU(2) spin Hamiltonians. In this Letter we generalize this construction to obtain a new class of SU(N) spin Hamiltonians. These Hamiltonians describe center-of-mass-position conserving pair hopping fermions in space dimension d>/=2.  相似文献   
999.
Lee CC  Wu K 《Optics letters》2007,32(15):2118-2120
We introduce a way to estimate the fluctuation of the refractive index during thin film deposition, through an optical monitor. The thicknesses and error-compensated thickness for each layer are analyzed. A novel monitoring method is thereby derived. The revised refractive index and the choice of highly sensitive monitoring wavelengths help us predict the termination points more accurately. The performance of a narrow-bandpass filter monitored by this method is demonstrated.  相似文献   
1000.
We have fabricated a solution-processed ZnO thin-film transistor without vacuum deposition. ZnO nanoparticles were prepared by the polyol method from zinc acetate, polyvinyl pyrrolidone, and diethyleneglycol. The solution-processable semiconductor ink was prepared by dispersing the synthesized ZnO in a solvent. Inverted stagger type thin-film transistors were fabricated by spin casting the ZnO ink on the heavily doped Si wafer with 200 nm thick SiO2, followed by evaporation of Cr/Au source and drain electrodes. After the drying and heat treatment at 600 C, a relatively dense ZnO film was obtained. The film characteristics were investigated by scanning electron microscopy (SEM) and X-ray diffraction (XRD). In order to obtain the electrical properties of the solution-derived transistor, the on–off ratio, threshold voltage, and mobility were measured.  相似文献   
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