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1.
A thermodynamic study of carbon dioxide adsorption on a zeolite‐templated carbon (ZTC), a superactivated carbon (MSC‐30), and an activated carbon (CNS‐201) was carried out at temperatures from 241 to 478 K and pressures up to 5.5?106 Pa. Excess adsorption isotherms were fitted with generalized Langmuir‐type equations, allowing the isosteric heats of adsorption and adsorbed‐phase heat capacities to be obtained as a function of absolute adsorption. On MSC‐30, a superactivated carbon, the isosteric heat of carbon dioxide adsorption increases with occupancy from 19 to 21 kJ?mol?1, before decreasing at high loading. This increase is attributed to attractive adsorbate–adsorbate intermolecular interactions as evidenced by the slope and magnitude of the increase in isosteric heat and the adsorbed‐phase heat capacities. An analysis of carbon dioxide adsorption on ZTC indicates a high degree of binding‐site homogeneity. A generalized Law of Corresponding States analysis indicates lower carbon dioxide adsorption than expected. © 2017 American Institute of Chemical Engineers AIChE J, 64: 1026–1033, 2018  相似文献   
2.
Although rapid smoking has proved to be a successful treatment strategy for smokers, its hazard potential has been recently debated. In the present study, 6 Ss (mean age 30.8 yrs) were monitored throughout 8 standard sessions of rapid smoking. Heart rate, blood pressure, and carboxyhemoglobin increases were generally higher than those reported in the few extant physiological studies of rapid smoking, and EKG abnormalities occurred in several Ss during rapid smoking. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
3.
Granulosa cells from small (less than 2mm) antral porcine follicles were grown in culture to study the effects of various hormones on growth, morphology and progesterone secretion. Culture medium 199D + 4% serum was found to be most suitable since it maintained a fairly constant cell population. Estradiol (1mug/ml) and human FSH stimulated cell growth. LH and FSH stimulated progesterone secretion and induced morphological changes associated with luteinization. Estradiol (0.1 mug/ml) inhibited progesterone secretion by granulosa cells.  相似文献   
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5.
Inner shell edge profiles for K, L and M edges that are most likely to be used in microanalysis have been calculated using Hartree-Slater wave functions and are compared to experimental data. The aim is to identify those features that are not predicted by a one-electron atomic theory and to get some estimate of the accuracy of quantitative analysis using these calculations. In general, the fit between theory and experiment is quite good for those edges which do not have maxima delayed by more than 40 eV. In addition, solid state effects are averaged out if large (100 eV) integration windows are used. Accuracy can be improved in the transition metals and the rare earths by excluding the “white line” portion of the spectrum in any comparison.  相似文献   
6.
Quantitative measurement of tumor blood flow with [15O]water can be used to evaluate the effects of tumor treatment over time. Since quantitative flow measurements require an input function, we developed the profile fitting method (PFM) to measure the input function from positron emission tomography images of the aorta. First, a [11C]CO scan was acquired and the aorta region was analyzed. The aorta diameter was determined by fitting the image data with a model that includes scanner resolution, the measured venous blood radioactivity concentration, and the spillover of counts from the background. The diameter was used in subsequent fitting of [15O]water dynamic images to estimate the aorta and background radioactivity concentrations. Phantom experiments were performed to test the model. Image quantification biases (up to 15%) were found for small objects, particularly for those in a large elliptical phantom. However, the bias in the PFM concentration estimates was much smaller (2%-6%). A simulation study showed that PFM had less bias and/or variability in flow parameter estimates than an ROI method. PFM was applied to human [11C]CO and [15O]water dynamic studies with left ventricle input functions used as the gold standard. PFM parameter estimates had higher variability than found in the simulation but with minimal bias. These studies suggest that PFM is a promising technique for the noninvasive measurement of the aorta [15O]water input function.  相似文献   
7.
自从3G被发明以来,人们就预料到在大移动厂商中间将产生巨大的震荡,但很少有人预料到发生这些变化的速度。诺基亚-西门子之间的交易所签的合同油墨未干,阿尔卡特和朗讯的股东刚刚认可了二者之间的合并,阿尔卡特这家法国厂商就着手购买北电的UMTS无线电网络控制器以及Node B产品包。这两项大的合并是可以预想到的。北电的交易清楚地显示了厂商试图在一个萎缩的市场上谋求大的基础设施合同时所面临的问题。不甘落后、跟同行比比高低就够受的了,再计算在HSPA及LTE中运营商所需要的投资则是一件更棘手的事。显然,对北电来说,这个答案很简…  相似文献   
8.
An enzyme immobilization technique employing enzyme sequestration within the porous support regions of asymmetric hollow fiber membranes is described and experimentally evaluated. Reactor conversion data over a wide range of operating conditions agrees well with predictions obtained from a mathematical model developed previously. β-galactosidase immobilized by this technique was found to retain 100% activity for 60 hours of continuous reactor operation, and for 140 days when stored at 3°C. The effects on reactor performance of (1) enzyme adsorption by the membrane, and (2) axial redistribution of enzyme accompanying radial flow of fluid through the fiber wall, have been evaluated; neither process significantly alters conversion kinetics or efficiency for the substrate/enzyme system investigated.  相似文献   
9.
The Mössbauer effect has been used to examine the phases produced by hydrogen reduction of hematite to α-iron at 535° C. No evidence has been found for spinels other than that of essentially stoichiometric magnetite; nor has there been any evidence of wüstite formation, in contrast to recent Russian experiments on the reduction of iron oxides at temperatures well below the eutectoid transition point of 570° C.  相似文献   
10.
We calculate the fidelity with which an arbitrary state can be encoded into a [7, 1, 3] Calderbank-Shor-Steane quantum error correction code in a non-equiprobable Pauli operator error environment with the goal of determining whether this encoding can be used for practical implementations of quantum computation. The determination of usability is accomplished by applying ideal error correction to the encoded state which demonstrates the correctability of errors that occurred during the encoding process. We also apply single-qubit Clifford gates to the encoded state and determine the accuracy with which these gates can be implemented. Finally, fault tolerant noisy error correction is applied to the encoded states allowing us to compare noisy (realistic) and perfect error correction implementations. We find the encoding to be usable for the states ${|0\rangle, |1\rangle}$ , and ${|\pm\rangle = |0\rangle\pm|1\rangle}$ . These results have implications for when non-fault tolerant procedures may be used in practical quantum computation and whether quantum error correction must be applied at every step in a quantum protocol.  相似文献   
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