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71.
A method for the differential staining of conventionally fixed paraffin-embedded woody plant tissue is described. A five-component stain combination is used with Bismarck Brown, included to avoid the stain variability, precipitation, and overstaining problems often encountered when using safranin.  相似文献   
72.
An electronic model, based upon reported physiological and anatomical findings and capable of replicating the optical-to-electrical transformations performed by the avian retina has been constructed.  相似文献   
73.
Ly SY  Chae JI  Jung YS  Jung WW  Lee HJ  Lee SH 《Die Nahrung》2004,48(3):201-204
A method for the detection of ascorbic acid (AA) was developed using square wave anodic stripping voltammetric (SWASV) analysis with a glassy carbon electrode (GCE). The results indicated a sensitive oxidation peak current of AA on the GCE. A linear curve was obtained within a concentration range of 1-130.0 microg/L with a preconcentration time of 270 s. The relative standard deviation of 30.0 microg/L observed was 0.1016% (n = 12) under optimum conditions. The low detection limit (S/N) was pegged at 0.30 microg/L. Results showed that the method developed can be used to assay biological and pharmaceutical samples, and food samples, as well as other materials requiring AA analyses.  相似文献   
74.
An aggressive dialysis in a grossly azotemic patient, especially one with severe metabolic acidosis, can lead to dialysis disequilibrium syndrome (DDS). Mild forms present as nausea, vomiting, restlessness, and headache. Severe manifestations include seizures, obtundation, coma, and even death. This clinical picture is caused by cerebral edema induced by one or more of the following mechanisms:
    相似文献   
75.
Objective: The University of Rhode Island Change Assessment (URICA) Scale has been widely used to assess the readiness to change with regard to various health-related behaviors. The present study aimed to develop a Chinese version of the URICA (C-URICA) for measuring the readiness to change of Chinese participants with chronic diseases. Participants: A group of participants (N=101; 87 women and 14 men) in a chronic disease self-management program were asked to complete the C-URICA. Method: The C-URICA was conducted at the baseline, middle, and end of the 6-week program. Changes in self-management behaviors were also measured. Results: Factor analyses revealed a moderate item-to-subscale fit, indicating that structural validity was retained. Item analyses suggested a moderate item quality. The C-URICA subscales can differentially and effectively predict participants' gains in self-management behaviors at the completion of the intervention program. Conclusion: The C-URICA is suitable for use among Chinese patients with chronic diseases. Further studies should explore the generalizability of the results to different diagnostic groups and subgroups among Chinese populations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
76.
The objective of this study was to investigate the degradability of linear low‐density polyethylene (LLDPE)/(soya powder) blends. The blends were compatibilized by epoxidized natural rubber with 50 mol% of epoxidation. They were exposed to a natural compost medium located in northern Malaysia. The degradability was evaluated by using tensile tests, a morphological study, carbonyl indices, crystallinity measurements, weight loss, and molecular‐weight changes. The tensile strength and elongation at break of the compatibilized blends decreased during one year of exposure. The colonization of fungus and the formation of pores were observed in micrographs. The carbonyl indices, crystallinity, and weight loss increased during exposure, thereby indicating the degradation of the blends. The reduction in molecular weight revealed the degradation of the LLDPE upon composting. Surprisingly, after composting, the compatibilized blends showed more degradation than the uncompatibilized ones. J. VINYL ADDIT. TECHNOL., 20:42–48, 2014. © 2014 Society of Plastics Engineers  相似文献   
77.
Chemical modification of plasticized meat and bone meal (MBM) and its thermal processing into bioplastic sheets is reported. Specifically, MBM plasticized with 30 wt% glycerol and modified with calcium hydroxide (CH) (0, 3, 7, and 10 wt%) was batch compounded at 100°C, 15–30 min, and 60 rpm followed by thermal compaction at 140°C to produce sheets. The effect of CH content on the chemical structure, processability, and tensile properties (static and dynamic) of modified MBM sheets were studied. Fine particle size of MBM and moderate environment humidity produced well‐consolidated sheets. Increase in CH content to about 7 wt% was found to increase tensile strength and modulus, whereas the strain to failure decreased. Fourier transform infrared spectroscopy analysis of modified MBM sheets showed that the changes in mechanical properties could be attributed to increased interactions between protein chains, which were further aided by the precipitation of the fat portion of MBM. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   
78.
79.
Alkyd-, oil-modified-latex-, and latex-based finishes were applied to severely weathered western redcedar and redwood boards that did not have any surface treatment to ameliorate the weathered surface prior to painting. Six finishes were evaluated annually for 11 years for cracking, flaking, erosion, mildew growth, discoloration, and general appearance. Lowsolids-content latex finishes that contained about 10% raw linseed oil and 11% acrylic resin (i.e., the oil-modified latex finishes) performed better on badly weathered wood than did the alkyd and the other latex finish, even after 11 years. Latex finishes that contained raw linseed oil probably stabilized the weathered surface and plasticized the finish. The stabilization of the wood surface and the flexibility of the finish throughout its service life are the important factors in finish performance on these weathered substrates. Forest Products Laboratory, One Gifford Pinchot Drive, Madison, WI 53705-2398. The use of trade or firm names in this publication is for reader information and does not imply endorsement by the U.S. Department of Agriculture of any product or service. The Forest Products Laboratory is maintained in cooperation with the University of Wisconsin. This article was written and prepared by U.S. Government employees on official time, and it is therefore in the public domain and not subject to copyright.  相似文献   
80.
Today flotation column has become an acceptable means of froth flotation for a fairly broad range of applications, in particular the cleaning of sulfides. Even after having been used for several years in mineral processing plants, the full potential of the flotation column process is still not fully exploited. There is no prediction of process performance for the complete use of available control capabilities. The on-line estimation of grade usually requires a significant amount of work in maintenance and calibration of on-stream analyzers, in order to maintain good accuracy and high availability. These difficulties and the high cost of investment and maintenance of these devices have encouraged the approach of prediction of metal grade and recovery. In this paper, a new approach has been proposed for metallurgical performance prediction in flotation columns using Artificial Neural Network (ANN). Despite of the wide range of applications and flexibility of NNs, there is still no general framework or procedure through which the appropriate network for a specific task can be designed. Design and structural optimization of NNs is still strongly dependent upon the designer’s experience. To mitigate this problem, a new method for the auto-design of NNs was used, based on Genetic Algorithm (GA). The new proposed method was evaluated by a case study in pilot plant flotation column at Sarcheshmeh copper plant. The chemical reagents dosage, froth height, air, wash water flow rates, gas holdup, Cu grade in the rougher feed, flotation column feed, column tail and final concentrate streams were used to the simulation by GANN. In this work, multi-layer NNs with Back Propagation (BP) algorithm with 8-17-10-2 and 8-13-6-2 arrangements have been applied to predict the Cu and Mo grades and recoveries, respectively. The correlation coefficient (R) values for the testing sets for Cu and Mo grades were 0.93, 0.94 and for their recoveries were 0.93, 0.92, respectively. The results discussed in this paper indicate that the proposed model can be used to predict the Cu and Mo grades and recoveries with a reasonable error.  相似文献   
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