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81.

Background, Aims and Scope

This study aims to compare the energy requirements and potential environmental impacts associated with three different commercial laundry processes for washing microbiologically contaminated hospital and care home laundry. Thermal disinfection relies mainly on a 90°C washing temperature and hydrogen peroxide, while the chemothermal disinfection uses a combination of chemicals (mainly peracetic acid) and 70°C washing temperature. The chemical disinfection process relies on a combination of chemicals used at 40°C. Currently, chemothermal processes are the most commonly used in professional laundries. Traditional chemical processes are uncommon due to drawbacks of longer residence time and high chemical requirements. However, the innovative Sterisan chemical process based on phthalimidoperoxyhexanoic acid (PAP) – which is the key subject of this Life Cycle Assessment – was designed to overcome these technical limitations.

Methods

This study is based on a screening Life Cycle Assessment (LCA) prepared in 2002 by Öko-Institut (Germany), which was carried out following the requirements of the ISO 14040 series standards. It includes energy resource consumption, water resource consumption, climate change, eutrophication and acidification potential as relevant environmental indicators. In 2004/2005, the study was further updated and broadened to include the aquatic eco-toxicity potential, photochemical oxidant formation and ozone depletion potential in order to represent the environmental burdens associated with the chemicals used.Based on available data, the system boundaries include detergent manufacturing, the professional wash process, waste water treatment, but excluding the laundry finishing process. The selected functional unit was 1kg washed hygiene laundry.

Results and Discussion

The LCA indicates that the Sterisan chemical process has a lower potential environmental impact than thermal or chemothermal treatment for six out of seven key indicators. This includes a 55% lower energy and a 46% lower water consumption. The global warming potential and acidification potential are approximately halved, while the photochemical oxidant formation potential and eutrophication potential are almost reduced to one third. By contrast, for the aquatic eco-toxicity, the thermal- and chemothermal processes have an approximately 17 fold lower impact. The worse aquatic toxicity score for the Sterisan process is mainly caused by a solvent component in the formulation.

Conclusion

The comparison of the thermal, chemothermal and Sterisan commercial laundry processes shows that the Sterisan process allows for very substantial reductions in energy and water consumption, as well as significant reductions in climate change, photochemical oxidant formation potential, air acidification potential and eutrophication potential. Yet, Sterisan has a clear disadvantage with regards to aquatic eco-toxicity potential.

Recommendation and Perspective

Based on a current hygiene laundry volume of approx. 584000 tons of linen washed per year by commercial laundries in Germany, a full substitution of the market to the Sterisan process could potentially allow a primary energy saving of ~750000 GJ/year (roughly equivalent to the residential primary energy consumption of 23500 German citizens or the overall energy demand of approx. 6000 German citizens). In terms of improvements to the respective processes, the chemothermal and thermal process could benefit from a reduction of water volume, and change of detergent composition to reduce the eutrophication potential. As the washing temperature is an essential factor, only slight improvements for the energy consumption indicator can be obtained, e.g. by choosing green electricity and reducing the amount of water to be heated. The Sterisan process could be improved by lowering the solvent use, although for perspective, the current aquatic eco-toxicity score of the Sterisan process is still lower than that of a typical domestic laundry product.
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83.
We have enriched a 47-kDa polypeptide (p47) from Neurospora crassa on the basis of its affinity to calmodulin. The p47 was purified to homogeneity by chromatography on a Mono S cation exchange column and evidence is presented that the polypeptide co-sediments specifically with F-actin. The intracellular distribution of p47 and actin was also examined using indirect double immunofluorescence staining of cells at different stages of development. Our results suggest that by altering the conformation binding site of actin to p47, calmodulin could play a regulatory role in the polarized hyphal growth of N. crassa.  相似文献   
84.
Aim Invasive alien species are a growing threat to biodiversity, and identifying the mechanisms that enable these species to establish viable populations in their new environment is paramount for management of the problems they pose. Using an unusually large number of both failed and successful documented introductions of parakeets (Aves: Psittacidae) in Europe, we test two of the major hypotheses on the establishment success of invading species, namely the climate‐matching and the human‐activity hypothesis. Location European human population centres where ring‐necked parakeet (Psittacula krameri) and/or monk parakeet (Myiopsitta monachus) introductions have occurred. Methods Data on ring‐necked and monk parakeet introductions in Europe were gathered from various sources, including published books and articles, but also from unpublished reports and local grey literature. Information was verified with experts from the region under consideration. In order to test the climate‐matching hypothesis, we verified whether the climatic factors that determine the parakeets’ native ranges also explain establishment success in Europe. Parakeet occurrence data from the native ranges were analysed using the presence‐only modelling method Maxent , and correlations between parakeet establishment and climatic and anthropogenic variables in Europe were assessed using both stepwise logistic regression and the information‐theoretic model selection approach. Results The establishment success of ring‐necked and monk parakeets was found to be positively associated with human population density, and, both in the native and in the introduced regions, parakeet occurrence was negatively correlated with the number of frost days. Thus, parakeets are more likely to establish in warmer and human‐dominated areas. Main conclusions The large number of independent parakeet introductions in Europe allows us to test the often‐used climate‐matching and human‐activity hypotheses at the species level. We show that both hypotheses offer insight into the invasion process of monk and ring‐necked parakeets. Our results suggest that, in the future, parakeet establishment probability may increase even further because global warming is likely to cause a decrease in the number of frost days and because urbanization and human populations are still increasing.  相似文献   
85.
86.
Summary An improved auto-analyzer method for the quantitative determination of phosphonate-phosphorus was developed. Its advantages are of three sorts: 1) phosphonates can be determined in a variety of media, even with high levels of organic compounds, 2) viscous bacterial broths can be analysed directly on the auto-analyzer, 3) the method has an increased sensitivity.  相似文献   
87.
Early growth of barley seedlings supplied with ion-depleted air in a controlled microenvironment was used as the criterion of physiological action in experiments designed to separate electrical field and air ion effects. The essential element in this work was the fact that3H foils, functioning as bias electrodes at applied voltages of 67.5-955 V and providing field strengths of 4.6 V/cm to 90 V/cm will produce 2.7×104–1.7×105 small air ions/cm3 — concentrations sufficient to yield a statistically valid increase in growth rate. In contrast, seedlings exposed to equivalent electrical fields in ion-depleted air exhibited no increase in rate of growth. These results indicate that this particular physiological response is produced by small negative air ions and is not dependent on the accompanying electrical fields.  相似文献   
88.

Background

CT perfusion (CTP) is used to estimate the extent of ischemic core and penumbra in patients with acute ischemic stroke. CTP reliability, however, is limited. This study aims to identify regions misclassified as ischemic core on CTP, using infarct on follow-up noncontrast CT. We aim to assess differences in volumetric and perfusion characteristics in these regions compared to areas that ended up as infarct on follow-up.

Materials and Methods

This study included 35 patients with >100 mm brain coverage CTP. CTP processing was performed using Philips software (IntelliSpace 7.0). Final infarct was automatically segmented on follow-up noncontrast CT and used as reference. CTP and follow-up noncontrast CT image data were registered. This allowed classification of ischemic lesion agreement (core on CTP: rMTT≥145%, aCBV<2.0 ml/100g and infarct on follow-up noncontrast CT) and misclassified ischemic core (core on CTP, not identified on follow-up noncontrast CT) regions. False discovery ratio (FDR), defined as misclassified ischemic core volume divided by total CTP ischemic core volume, was calculated. Absolute and relative CTP parameters (CBV, CBF, and MTT) were calculated for both misclassified CTP ischemic core and ischemic lesion agreement regions and compared using paired rank-sum tests.

Results

Median total CTP ischemic core volume was 49.7ml (IQR:29.9ml-132ml); median misclassified ischemic core volume was 30.4ml (IQR:20.9ml-77.0ml). Median FDR between patients was 62% (IQR:49%-80%). Median relative mean transit time was 243% (IQR:198%-289%) and 342% (IQR:249%-432%) for misclassified and ischemic lesion agreement regions, respectively. Median absolute cerebral blood volume was 1.59 (IQR:1.43–1.79) ml/100g (P<0.01) and 1.38 (IQR:1.15–1.49) ml/100g (P<0.01) for misclassified ischemic core and ischemic lesion agreement, respectively. All CTP parameter values differed significantly.

Conclusion

For all patients a considerable region of the CTP ischemic core is misclassified. CTP parameters significantly differed between ischemic lesion agreement and misclassified CTP ischemic core, suggesting that CTP analysis may benefit from revisions.  相似文献   
89.
Most plants grow in dense vegetation with the risk of being out-competed by neighboring plants. These neighbors can be detected not only through the depletion in light quantity that they cause, but also through the change in light quality, which plants perceive using specific photoreceptors. Both the reduction of the red:far-red ratio and the depletion of blue light are signals that induce a set of phenotypic traits, such as shoot elongation and leaf hyponasty, which increase the likelihood of light capture in dense plant stands. This set of phenotypic responses are part of the so called shade avoidance syndrome (SAS). This addendum discusses recent findings on the regulation of the SAS of Arabidopsis thaliana upon blue light depletion. Keller et al. and Keuskamp et al. show that the low blue light attenuation induced shade avoidance response of seedling and rosette-stage A. thaliana plants differ in their hormonal regulation. These studies also show there is a regulatory overlap with the R:FR-regulated SAS.  相似文献   
90.
We have previously developed and validated a prognostic model to predict the risk for unfavorable outcome in Dutch adults with bacterial meningitis. The aim of the current study was to validate this model in adults with bacterial meningitis from two developing countries, Vietnam and Malawi. Demographic and clinical characteristics of Vietnamese (n = 426), Malawian patients (n = 465) differed substantially from those of Dutch patients (n = 696). The Dutch model underestimated the risk of poor outcome in both Malawi and Vietnam. The discrimination of the original model (c-statistic [c] 0.84; 95% confidence interval 0.81 to 0.86) fell considerably when re-estimated in the Vietnam cohort (c = 0.70) or in the Malawian cohort (c = 0.68). Our validation study shows that new prognostic models have to be developed for these countries in a sufficiently large series of unselected patients.  相似文献   
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