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991.
It was found that a glutaraldehyde-formalin-phosphate buffered fixative could preserve retinal tissue for light microscopy, even if the tissue remained in the fixative for a month. Retinal tissue that previously was difficult and expensive to procure could now be obtained. 相似文献
992.
The effect of application pH on the effectiveness of the conventional cationic fixing agents Matexil FC-ER and Fixogene CXF in improving the wash fastness of the commercial direct dyes CI Direct Red 89, CI Direct Yellow 106 and CI Direct Blue 85 on cotton has been investigated. While the recommended neutral pH application resulted in improved fastness of the dyeings to the ISOC06/C2 wash fastness test, wash fastness was noticeably better when the fixing agents were applied under alkaline conditions. 相似文献
993.
Kerry L Porter Graham Collins Andreas Klieber 《Journal of the science of food and agriculture》2005,85(2):293-296
Chinese cabbages cv ‘Yuki’ (Brassica campestris L ssp pekinensis (Lour) Olsson) were treated with air containing 1‐methylcyclopropene (1‐MCP) at concentrations ranging from 0 to 1 µl l?1 for 12 h at 22°C before storage for 9 weeks at 3°C. Quality, weight loss and trimming loss were measured before treatment, and before and after storage, but were not influenced by 1‐MCP. 1‐MCP at 0.1 and 1.0 µl l?1 elicited increased levels of respiration and ethylene production which subsided when the cabbages were placed in cold storage. Copyright © 2004 Society of Chemical Industry 相似文献
994.
Digital imaging technologies have now developed to the point where engineers specializing in image systems engineering are needed in order for imaging to reach its full potential, In 1996, the University of Iowa launched a multiphase project for the development of a well-structured interdisciplinary image systems engineering curriculum with both depth and breadth in its offerings. This project has been supported by equipment grants from the Hewlett Packard Company. The new teaching approach that we are developing is very dissimilar to the blackboard-and-chalk approach we used in previous years. Utilizing a 40-seat electronic classroom, lectures consist of presentation of concepts, immediately followed by examples, and practical exploratory problems. Four image processing classes have been offered in the new collaborative learning environment during the 1996-1997 academic year. This paper outlines the employed educational approach we are taking and summarizes our experience in the first year 相似文献
995.
Multiple criteria analysis (MCA) is a framework for ranking or scoring the overall performance of decision options against
multiple objectives. The approach has widespread and growing application in the field of water resource management. This paper
reviews 113 published water management MCA studies from 34 countries. It finds that MCA is being heavily used for water policy
evaluation, strategic planning and infrastructure selection. A wide range of MCA methods are being used with the fuzzy set
analysis, paired comparison and outranking methods being most common. The paper also examines the motivations for adopting
MCA in water management problems and considers future research directions.
This study was funded by the eWater CRC (). 相似文献
996.
G Collins T Mahony A M Enright A Gieseke D de Beer V O'Flaherty 《Water science and technology》2007,55(8-9):369-376
Radiotracer incubation experiments and beta microimaging, along with fluorescent in situ hybridisation (FISH), are proposed as a complementary approach to specific methanogenic activity testing and measurement of in vitro substrate utilisation rates to understand better the ecophysiology of anaerobic granular biofilms from wastewater treatment reactors. 相似文献
997.
A Dunphy S Beecham S Vigneswaran H H Ngo R McLaughlan A Collins 《Water science and technology》2007,55(4):211-218
Innovative Water Sensitive Urban Design (WSUD) systems are being investigated at three locations to the north and south of Sydney, Australia. These systems contain porous concrete pipes that are designed so that stormwater exfiltrates through the permeable walls of the pipes into the surrounding substrate media material. The porous pipes and media material treat the passing stormwater. The primary aim of the overall project is to develop a model to describe the treatment effectiveness of confined WSUD systems. This paper focuses on the system located at the Weathertex Industrial Site, Heatherbrae. Due to wood processing operations that occur at this site, it is recognised that the surface runoff will carry a heavy organics loading. Granulated Activated Carbon (GAC) is recognised for its ability to reduce the concentration of dissolved organics present in both wastewater and stormwater. GAC was therefore chosen as a filtration medium to be investigated at this site. To maximise the effectiveness of the GAC, extensive laboratory batch studies were undertaken prior to the field system being constructed to determine the optimum GAC/sand ratio. The purpose of the experimental work was to assess the dissolved organic removal potential through sorption of various concentrations of GAC. The aim of this paper is to describe these laboratory experiments and discuss how they related to the field system. Through these experiments it was determined that a sand/GAC ratio of 25:1 was ideal for the media material at the Heatherbrae site. 相似文献
998.
Susan Essien Etok Eugenia Valsami-Jones Timothy J. Wess Jennifer C. Hiller Clark A. Maxwell Keith D. Rogers David A. C. Manning Margaret L. White Elisa Lopez-Capel Matthew J. Collins Mike Buckley Kirsty E. H. Penkman Stephen L. Woodgate 《Journal of Materials Science》2007,42(23):9807-9816
The thermal behaviour of the animal by-product meat and bone meal (MBM) has been investigated in order to assess how it is
affected structurally and chemically by incineration. Initially composed of intergrown collagen and hydroxyapatite (HAP),
combustion of the organic component is complete by 650 °C, with most mass loss (50–55%) occurring by 500 °C. No original proteins
were detected in samples heated at 400 °C or above. Combustion of collagen is accompanied by an increase in HAP mean crystallite
size at temperatures greater than 400 °C, from 10 nm to a constant value of 120 nm at 800 °C or more. Newly formed crystalline
phases appear beyond 400 °C, and include β-tricalcium phosphate, NaCaPO4, halite (NaCl) and sylvite (KCl). Crystallite thickness as judged by small angle X-ray scattering (SAXS) increases from 2 nm
(25–400 °C) to 8–9 nm very rapidly at 550 °C, and then gradually increases to approximately 10 nm. The original texture of
HAP within a collagen matrix is progressively lost, producing a porous HAP dominated solid at 700 °C, and a very low porosity
sintered HAP product at 900 °C. 相似文献
999.
D. Gopi V. Collins Arun Prakash L. Kavitha 《Materials science & engineering. C, Materials for biological applications》2009,29(3):955-958
Surgical grade stainless steel (316L SS) is one of the widely used implant material in orthopedic surgeries. But often the release of metal ions is evidenced from the implants and subsequently a second surgery is required to remove the implant material. One way to control this release of metal ions is to coat the implant material with a biocompatible material like hydroxyapatite. In this paper we have reported a successful coating of hydroxyapatite over borate passivated 316L SS by a dip coating method. The coatings were characterized by electrochemical techniques such as potentiodynamic polarization, electrochemical impedance and cyclic voltammetry (CV). Also X-ray diffraction (XRD) and scanning electron microscopic (SEM) studies were performed to confirm the quality of the coatings. Results of accelerated leach out characteristics by inductively coupled plasma–atomic emission spectroscopy (ICP–AES) and the evaluation of shear strength are also presented to support the corrosion resistant nature of the coatings. The enhanced bio-resistivity of the as-formed HAP coatings on passivated 316L SS is attributed to the protective passive layer formed by borate buffer solution at selected potentials. 相似文献
1000.
Data express gigabit junction with the next-generation Internet 总被引:1,自引:0,他引:1
Important as a very high-performance backbone is to the next generation of the Internet, it is no less important that the points at which people connect to the backbone-the so-called points of presence, or POPs-provide an equivalent level of performance. For almost three years, members of the academic, research, and business community in the North Carolina region known as the Research Triangle-the area lying amid the cities of Raleigh, Durham, and Chapel Hill-have been working to create a high-performance regional network. As partners in the North Carolina Network Initiative (NCNI), they have built a network that can serve as a POP handling the multigigabit traffic to be delivered by the next-generation Internet. Thence comes its name: a GigaPOP. Like a great railway junction, the GigaPOP is a central distribution point where huge amounts of digital freight are moved between various end points and the main line (such as the very high-performance Backbone Network Services, or VBNS). The NCNI is one of a handful of regional networking organizations around the country. The others include the California Research and Education Network 2 (Calren2), the Metropolitan REN (MREN) serving the Chicago area, the Houston Area Computational Science Consortium (HACSC), and the New York State Educational and Research Network (Nysernet). NCNI's work, which predates most initiatives for the Internet's second generation, serves as a model of how various regions can latch onto the coming information superhighway to good effect 相似文献