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1.
A. S. Paschoa M. E. Wrenn N. P. Singh F. W. Bruenger S. C. Miller M. Cholewa K. W. Jones 《Biological trace element research》1987,13(1):275-282
Several geological formations of the Utah-Colorado mining region mined for uranium ore during and after World War II had been
mined earlier for vanadium. Therefore, most miners and millers from that region were exposed to those metals’ ores or tailings
at one time or another. Preliminary investigation to determine uranium and vanadium retained in the lungs of a former uranium
miner and miller from this region, who died of lung cancer (mesothelioma), showed a high nonuniform distribution of vanadium.
This observation led to the hypothesis that the vanadium content in the lungs could be associated with inhaled particles.
Further examination of spectra of characteristic X-rays obtained by scanning particle-induced X-ray emission (microPIXE) of
an autopsy sample of this lung indicated that vanadium was indeed present in localized sites within the 20-μm spatial resolution
of the proton beam. This work points out that the microPIXE-RBS (Rutherford backscattering) test for vanadium can be used
for site localization of inhaled particles retained in the lungs. Further studies are in progress to: (i) locate uranium-bearing
particles in lung tissues of former uranium miners and millers; and (ii) evaluate the local doses of alpha radiation received
from these particles. 相似文献
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3.
Bracketed generic inactivation of rodent retroviruses by low pH treatment for monoclonal antibodies and recombinant proteins 总被引:6,自引:0,他引:6
Brorson K Krejci S Lee K Hamilton E Stein K Xu Y 《Biotechnology and bioengineering》2003,82(3):321-329
Viral safety is a predominant concern for monoclonal antibodies (mAbs) and other recombinant proteins (RPs) with pharmaceutical applications. Certain commercial purification modules, such as nanofiltration and low-pH inactivation, have been observed to reliably clear greater than 4 log(10) of large enveloped viruses, including endogenous retrovirus. The concept of "bracketed generic clearance" has been proposed for these steps if it could be prospectively demonstrated that viral log(10) reduction value (LRV) is not impacted by operating parameters that can vary, within a reasonable range, between commercial processes. In the case of low-pH inactivation, a common step in mAb purification processes employed after protein A affinity chromatography, these parameters would include pH, time and temperature of incubation, the content of salts, protein concentration, aggregates, impurities, model protein pI, and buffer composition. In this report, we define bracketed generic clearance conditions, using a prospectively defined bracket/matrix approach, where low-pH inactivation consistently achieves >or=4.6 log(10) clearance of xenotropic murine leukemia virus (X-MLV), a model for rodent endogenous retrovirus. The mechanism of retrovirus inactivation by low-pH treatment was also investigated. 相似文献
4.
Recent environmental trends, including (1) an expansion of existing command and control directives, (2) the introduction of market‐based policy instruments, and (3) the adoption of extended producer responsibility, have created a need for new tools to help managerial decision‐making. To address this need, we develop a nonlinear mathematical programming model from a profit‐maximizing firm's perspective, which can be tailored as a decision‐support tool for firms facing environmental goals and constraints. We typify our approach using the specific context of diesel engine manufacturing and remanufacturing. Our model constructs are based on detailed interviews with top managers from two leading competitors in the medium and heavy‐duty diesel engine industry. The approach allows the incorporation of traditional operations‐planning considerations—in particular, capacity, production, and inventory—together with environmental considerations that range from product design through production to product end of life. A current hurdle to implementing such a model is the availability of input data. We therefore highlight the need not only to involve all departments within businesses but also for industrial ecologists and business managers to work together to implement meaningful decision models that are based on accurate and timely data and can have positive economic and environmental impact. 相似文献
5.
M Sinigaglia M Albenzio M Rosaria Corbo 《Journal of industrial microbiology & biotechnology》1999,23(6):484-488
Cut lettuce salads and shredded carrots were prepared according to four different procedures in order to determine the influence
of various operations on the shelf-life of these ‘minimally processed’ foods. In particular, the level of active chlorine
used or its residue after washing as well as the processing time were considered. The results emphasize the role of free chlorine
in reduction of the contamination level and its effectiveness toward Pseudomonadaceae and Enterobacteriaceae. Moreover a 12-h delay without refrigeration, after pre-washing or removal of ends, caused a lengthening of the processing
time, enough to allow microbial proliferation and subsequent shortening of shelf-life. Shelf-life extension and the improvement
of safety and quality of these products can be obtained by means of adequate processing operations.
Received 29 September 1998/ Accepted in revised form 19 July 1999 相似文献
6.
以台湾‘长香’辣椒Capsicum frutescens品种为材料,通过设置钾肥横向与纵向施肥的田间试验,探讨辣椒最佳钾肥用量及其运筹。结果表明,在设定氮、磷肥施用量分别为15.0、3.5 kg·667m-2的条件下,钾肥不同施用量对辣椒的株高、幅宽、茎粗的长势及果长、果粗、单果重等品质均有明显的影响,辣椒产量(y)与钾肥施用量(x)两者呈y = -2.2743x2 + 53.402x + 802.45的相关性(r2 = 0.973),钾肥最佳施用量为11.74 kg·667m-2;在同样条件下,钾肥施用量12.00 kg·667m-2,按基肥与追肥不同比例进行施用,辣椒株高、幅宽、茎粗的长势及果长、果粗、单果重等品质与产量均有所差异,其基肥∶追肥按2∶8的配比进行运筹施用,辣椒品质与产量均明显优于其他配比。 相似文献
7.
Christian Capello Gregor Wernet Jürgen Sutter Stefanie Hellweg Konrad Hungerbühler 《The International Journal of Life Cycle Assessment》2009,14(5):467-479
Background, aim, and scope Organic solvents are used in large quantities in the chemical, metal and electronics industries as well as in many consumer
products, such as coatings or paints, and are therefore among the most important chemicals. The petrochemical production of
organic solvents is a relevant environmental issue because fossil resources are needed (crude oil and natural gas), synthesis
processes are energy-intensive and cause considerable amounts of emissions. So far, comprehensive data on the environmental
impact are rather scarce. The aim of this paper is to therefore present a systematical environmental assessment of the main
petrochemical solvent production routes using the Life Cycle Assessment (LCA) method.
Methods Fifty organic solvents were selected covering the most important representatives from the various chemical groups (e.g., alcohols,
esters, ketones). To conduct the LCA, 40 new Life Cycle Inventories (LCI) were established and existing LCI were improved.
The petrochemical solvent production was structured into four production routes. In these production routes, the single chemical
unit processes (e.g. esterification, carbonylation or hydrogenation) were analyzed in order to determine characteristic environmental
impacts.
Results and discussion The four solvent production routes including the unit processes and intermediates are presented. Additionally, energy profiles
of these production routes are shown using the Cumulative Primary Energy Demand (CED) as an indicator for the environmental
impact. The results were cross-checked with the Global Warming Potential and the Eco-indicator 99 method and good correlations
were found. Processes that show high environmental impacts are the dehydration of butylene glycol to tetrahydrofuran, the
carbonylation of methanol to methyl formate, the hydrogenation of acetone to methyl isobutyl ketone, and the Reppe synthesis
of formaldehyd/acetylene to butylene glycol. Based on the energy profiles, ranges of environmental impacts are determined
for all unit processes. On the one hand, esterification and alkylation processes cause high CED values because complex ancillaries
are needed and hydroformylation and carbonylation processes are energy-intensive. On the other hand, in hydration, hydrogenation,
hydrolysis, and oxidation processes, ancillaries with low CED are added to the chemical structure that result in low CED ranges
for these unit processes. Dehydrogenation and molecular sieve separation processes seem to be energy efficient and no ancillaries
are required. Therefore, these unit processes cause the lowest CED values.
Perspectives Subject of further research in this field should be the environmental analysis of further process steps that include the presented
unit processes and a subsequent statistical analysis in order to derive reliable data ranges for all unit processes. Such
statistically robust ranges could be used in the approximation of missing life-cycle inventory data of other chemical products
and intermediates.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
8.
Same Supply Chain,Different Models: Integrating Perspectives from Life Cycle Assessment and Supply Chain Management 下载免费PDF全文
Within industrial ecology, there is a substantial community focusing on life cycle assessment (LCA) and corresponding tools and methods. Within the field of supply chain management, an increasing community is converging around sustainable supply chains. These two communities study the same underlying systems, but bring different perspectives to bear. We review seven issues that arise at this intersection of LCA and supply chain management, with the aim of illustrating how both communities can enrich each other by closer interaction. We conclude with some suggestions for how the two communities can further collaborate. 相似文献
9.
Eco-efficiency has been established as a crucial concept for corporate environmental management. Most approaches deal with eco-efficiency on the level of the company or the product. However, given that companies have special budgets earmarked for environmental operations or investments, the question arises as to which operation within which domain is the most eco-efficient. This article presents an approach to supporting these decisions by calculating eco-efficiency on the operational level. The procedure is demonstrated using a case study of the Swiss National Railway Company. Investments and operations in the domains of energy production, landscape and nature conservation, noise protection, and contaminated soil remediation are assessed and compared. Decision-makers seeking an eco-efficient corporate investment policy will find, in this concept, a guideline for prioritizing various domains of operation as well as the operations within a domain. 相似文献
10.
David Parsons 《The International Journal of Life Cycle Assessment》2009,14(2):175-183
Background, aim, and scope The process of producing a graduate is a complex one involving major effort usually by large institutions such as universities.
The Faculty of Engineering and Surveying at the University of Southern Queensland, Australia produces several hundred engineering
and spatial science graduates each year using both on-campus and external modes of study. The purpose of this study is to
determine the major causes of environmental impact in this process with a view to targeting areas where improvements may be
made.
Materials and methods An inventory of all major inputs to and outputs from the faculty was compiled from a mixture of measurements, real data, and
financial data for the calendar year 2006. Data for graduate output were also compiled. These data were then assessed using
SimaPro software, mainly Australian data and predominantly the Eco-indicator 99 (E) method of impact assessment.
Results The analysis shows that environmental impacts are many and varied as might be expected from a complex operation like a university.
However, energy inputs in the form of electricity from black coal, staff and student travel and the embodied impact of buildings
were dominant.
Discussion The results obtained may point the way towards future consideration of areas where environmental impact might be reduced by
changes in institution strategies such as the way external students are taught and the way the electricity usage in our buildings
is managed.
Conclusions The environmental impact of undergraduate education is complex and involves many different areas of activity. However, the
use of energy in various forms is of major significance in this impact.
Recommendations and perspectives It is recommended that university managers consider the results presented in this paper and use them as a starting point in
developing strategies to reduce the impact of their institutions. 相似文献