共查询到20条相似文献,搜索用时 31 毫秒
1.
Saeed Ghafghazi Taraneh Sowlati Shahab Sokhansanj Xiaotao Bi Staffan Melin 《The International Journal of Life Cycle Assessment》2011,16(3):212-223
Purpose
There has been an increased interest in utilizing renewable energy sources in district heating systems. District heating systems are centralized systems that provide heat for residential and commercial buildings in a community. While various renewable and conventional energy sources can be used in such systems, many stakeholders are interested in choosing the feasible option with the least environmental impacts. This paper evaluates and compares environmental burdens of alternative energy source options for the base–load of a district heating center in Vancouver, British Columbia (BC) using the life cycle assessment method. The considered energy sources include natural gas, wood pellet, sewer heat, and ground heat. 相似文献2.
Christian Solli Marte Reenaas Anders Hammer Strømman Edgar G. Hertwich 《The International Journal of Life Cycle Assessment》2009,14(6):517-528
Background, aim, and scope
In this study, we evaluate the environmental effects of wood-based household heating. Wood is a significant source of household heating in Norway, and a comparative life cycle assessment of a wood-based heating system using an old and a modern stove was conducted to estimate the total life cycle benefits associated with the change from old to new combustion technology. 相似文献3.
Mike Placinta Meng-Chieh Shen Marc Achermann Rolf O Karlstrom 《BMC developmental biology》2009,9(1):73
Background
Tissue heating has been employed to study a variety of biological processes, including the study of genes that control embryonic development. Conditional regulation of gene expression is a particularly powerful approach for understanding gene function. One popular method for mis-expressing a gene of interest employs heat-inducible heat shock protein (hsp) promoters. Global heat shock of hsp-promoter-containing transgenic animals induces gene expression throughout all tissues, but does not allow for spatial control. Local heating allows for spatial control of hsp-promoter-driven transgenes, but methods for local heating are cumbersome and variably effective. 相似文献4.
Akio Kanezaki Akimasa Hirata Soichi Watanabe Hiroshi Shirai 《Biomedical engineering online》2009,8(1):20-9
Background
Because the possibility of millimeter wave (MMW) exposure has increased, public concern about the health issues due to electromagnetic radiation has also increased. While many studies have been conducted for MMW exposure, the effect of dielectric permittivities on skin heating in multilayer/heterogeneous human-body models have not been adequately investigated. This is partly due to the fact that a detailed investigation of skin heating in a multilayer model by computational methods is difficult since many parameters are involved. In the present study, therefore, theoretical analyses were conducted to investigate the relationship between dielectric permittivities and MMW-induced skin heating in a one-dimensional three-layer model (skin, fat, and muscle). 相似文献5.
Goal, Scope and Background
District heating, the utilization of centrally produced heat for space heating and domestic hot water generation, has the potential to contribute to the eco-efficient use of energy resources in the parts of the world where space heating is needed. In literature, environmental studies on district heating mainly consider the emissions from heat generation; the environmental impact from the distribution system is seldom discussed. This paper presents a life cycle assessment of the production of district heating pipes, based on a cradle-to-gate life cycle inventory commissioned by the Swedish District Heating Association. No external review has been performed but a reference group of district heating experts familiar with the practice was involved in the choice of cases as well as in reviewing parts of the study. 相似文献6.
Background
Temperature is a frequently used parameter to describe the predicted size of lesions computed by computational models. In many cases, however, temperature correlates poorly with lesion size. Although many studies have been conducted to characterize the relationship between time-temperature exposure of tissue heating to cell damage, to date these relationships have not been employed in a finite element model. 相似文献7.
David Parsons 《The International Journal of Life Cycle Assessment》2010,15(8):785-793
Background, aim, and scope
Home heating is an important component of life in inland temperate Australia, and firewood remains a common and relatively inexpensive fuel. However, supplies of firewood are becoming scarce, and excessive smoke pollution is becoming a problem in some places, partly due to poor management of fires. The alternative energy sources are electricity and gas, and the aim of this study is to compare the relative merits of these three energy sources for their impacts on the physical environment. 相似文献8.
Paulo A Garcia John H RossmeislJr Robert E NealII Thomas L Ellis Rafael V Davalos 《Biomedical engineering online》2011,10(1):34
Background
Irreversible electroporation (IRE) is a new minimally invasive technique to kill undesirable tissue in a non-thermal manner. In order to maximize the benefits from an IRE procedure, the pulse parameters and electrode configuration must be optimized to achieve complete coverage of the targeted tissue while preventing thermal damage due to excessive Joule heating. 相似文献9.
Background
Techniques based on radio frequency (RF) energy have many applications in medicine, in particular tumour ablation. Today, mammography screening detects many breast cancers at an early stage, facilitating treatment by minimally invasive techniques such as radio frequency ablation (RFA). The breast cancer is mostly surrounded by fat, which during RFA-treatment could result in preferential heating of the tumour due to the substantial differences in electrical parameters. The object of this study was to investigate if this preferential heating existed during experimental in vitro protocols and during computer simulations. 相似文献10.
Background
Bioleaching is a process that has been used in the past in mineral pretreatment of refractory sulfides, mainly in the gold, copper and uranium benefit. This technology has been proved to be cheaper, more efficient and environmentally friendly than roasting and high pressure moisture heating processes. So far the most studied microorganism in bioleaching is Acidithiobacillus ferrooxidans. There are a few studies about the benefit of metals of low value through bioleaching. From all of these, there are almost no studies dealing with complex minerals containing arsenopyrite (FeAsS). Reduction and/or elimination of arsenic in these ores increase their value and allows the exploitation of a vast variety of minerals that today are being underexploited. 相似文献11.
Christopher J Gannon Chitta Ranjan Patra Resham Bhattacharya Priyabrata Mukherjee Steven A Curley 《Journal of nanobiotechnology》2008,6(1):2
Background
Novel approaches to treat human cancer that are effective with minimal toxicity profiles are needed. We evaluated gold nanoparticles (GNPs) in human hepatocellular and pancreatic cancer cells to determine: 1) absence of intrinsic cytotoxicity of the GNPs and 2) external radiofrequency (RF) field-induced heating of intracellular GNPs to produce thermal destruction of malignant cells. GNPs (5 nm diameter) were added to 2 human cancer cell lines (Panc-1, Hep3B). 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and propidium iodide-fluorescence associated cell sorting (PI-FACS) assessed cell proliferation and GNP-related cytotoxicity. Other GNP-treated cells were exposed to a 13.56 MHz RF field for 1, 2, or 5 minutes, and then incubated for 24 hours. PI-FACS measured RF-induced cytotoxicity. 相似文献12.
13.
Jinghuan Li Paul Smyth Susanne Cahill Karen Denning Richard Flavin Sinead Aherne Marco Pirotta Simone M Guenther John J O'Leary Orla Sheils 《BMC biotechnology》2008,8(1):10
Background
Archival formalin-fixed paraffin-embedded (FFPE) tissues represent an abundant source of clinical specimens; however their use is limited in applications involving analysis of gene expression due to RNA degradation and modification during fixation and processing. This study improved the quality of RNA extracted from FFPE by introducing a heating step into the selected extraction protocols. Further, it evaluated a novel pre-amplification system (PreAmp) designed to enhance expression analysis from tissue samples using assays with a range of amplicon size (62–164 bp). 相似文献14.
Daniele Cespi Fabrizio Passarini Luca Ciacci Ivano Vassura Valentina Castellani Elena Collina Andrea Piazzalunga Luciano Morselli 《The International Journal of Life Cycle Assessment》2014,19(1):89-99
Purpose
Biomass provides an attractive solution for residential heating systems based on renewable fuels, even though biomass-based domestic heating systems are recognized as significant particulate matter emitters; thus, a life cycle assessment (LCA) approach was used in the study to compare two different appliances: a wood stove and a pellet stove, both modeled according to the best available technologies definition.Methods
System boundaries of each scenario refer to a cradle-to-grave approach, including production, use and disposal of the heating appliance, as well as the preparation of biomass feedstock. The assessment of environmental impacts was performed assuming 1 MJ of thermal energy as the reference flow, considering the categories of particulate matter formation, human toxicity, climate change, and fossil fuel depletion, according to the ReCiPe 1.07 method. Finally, the comparison was extended to certain innovative heating systems in order to qualitatively evaluate potential improvements in residential heating performances.Results and discussion
The results show that the wood stove reaches the highest scores in the categories of particulate matter formation and negative effects for human toxicity, as a consequence of the stove’s lower combustion efficiency, which would lead to a preference for the pellet stove. However, when climate change affecting human health and the ecosystem, and fossil depletion are considered, the choice appears more uncertain due to the energy consumption from the pelletizing step. Alternative technologies (e.g., solar panels in combination with a gas boiler) show better scores related to fine particles emission reduction, even if a worsening in other categories is observed. The results were validated by a sensitivity analysis.Conclusions
The study suggests that a LCA approach can support the choice of the best domestic heating system, helping to promote policy initiatives on a sound basis and to understand which are the main key levers to act for reducing the total environmental burdens of biomass-based heating appliances. 相似文献15.
Background
Keeping abdominal surgery patients warm is common and warming methods are needed in power outages during natural disasters. We aimed to evaluate the efficacy of low-cost, low-power warming methods for maintaining normothermia in abdominal surgery patients.Methods
Patients (n = 160) scheduled for elective abdominal surgery were included in this prospective clinical study. Five warming methods were applied: heated blood transfusion/fluid infusion vs. unheated; wrapping patients vs. not wrapping; applying moist dressings, heated or not; surgical field rinse heated or not; and applying heating blankets or not. Patients’ nasopharyngeal and rectal temperatures were recorded to evaluate warming efficacy. Significant differences were found in mean temperatures of warmed patients compared to those not warmed.Results
When we compared temperatures of abdominal surgery patient groups receiving three specific warming methods with temperatures of control groups not receiving these methods, significant differences were revealed in temperatures maintained during the surgeries between the warmed groups and controls.Discussion
The value of maintaining normothermia in patients undergoing abdominal surgery under general anesthesia is accepted. Three effective economical and practically applicable warming methods are combined body wrapping and heating blanket; combined body wrapping, heated moist dressings, and heating blanket; combined body wrapping, heated moist dressings, and warmed surgical rinse fluid, with or without heating blanket. These methods are practically applicable when low-cost method is indeed needed. 相似文献16.
Antibacterial and antifungal activities of pyroligneous acid from wood of Eucalyptus urograndis and Mimosa tenuiflora
下载免费PDF全文
![点击此处可从《Journal of applied microbiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
E. de Souza Araújo A.S. Pimenta F.M.C. Feijó R.V.O. Castro M. Fasciotti T.V.C. Monteiro K.M.G. de Lima 《Journal of applied microbiology》2018,124(1):85-96
Aims
This work aimed to evaluate the antibacterial and antifungal activities of two types of pyroligneous acid (PA) obtained from slow pyrolysis of wood of Mimosa tenuiflora and of a hybrid of Eucalyptus urophylla × Eucalyptus grandis.Methods and Results
Wood wedges were carbonized on a heating rate of 1·25°C min?1 until 450°C. Pyrolysis smoke was trapped and condensed to yield liquid products. Crude pyrolysis liquids were bidistilled under 5 mmHg vacuum yielding purified PA. Multi‐antibiotic‐resistant strains of Escherichia coli, Pseudomonas aeruginosa (ATCC 27853) and Staphylococcus aureus (ATCC 25923) had their sensitivity to PA evaluated using agar diffusion test. Two yeasts were evaluated as well, Candida albicans (ATCC 10231) and Cryptococcus neoformans. GC‐MS analysis of both PAs was carried out to obtain their chemical composition. Regression analysis was performed, and models were adjusted, with diameter of inhibition halos and PA concentration (100, 50 and 20%) as parameters. Identity of regression models and equality of parameters in polynomial orthogonal equations were verified. Inhibition halos were observed in the range 15–25 mm of diameter.Conclusions
All micro‐organisms were inhibited by both types of PA even in the lowest concentration of 20%.Significance and Impact of the Study
The feasibility of the usage of PAs produced with wood species planted in large scale in Brazil was evident and the real potential as a basis to produce natural antibacterial and antifungal agents, with real possibility to be used in veterinary and zootechnical applications. 相似文献17.
Kayo Kudo Eri Nabeshima Shahanara Begum Yusuke Yamagishi Satoshi Nakaba Yuichiro Oribe Koh Yasue Ryo Funada 《Annals of botany》2014,113(6):1021-1027
Background and Aims
The networks of vessel elements play a vital role in the transport of water from roots to leaves, and the continuous formation of earlywood vessels is crucial for the growth of ring-porous hardwoods. The differentiation of earlywood vessels is controlled by external and internal factors. The present study was designed to identify the limiting factors in the induction of cambial reactivation and the differentiation of earlywood vessels, using localized heating and disbudding of dormant stems of seedlings of a deciduous ring-porous hardwood, Quercus serrata.Methods
Localized heating was achieved by wrapping an electric heating ribbon around stems. Disbudding involved removal of all buds. Three treatments were initiated on 1 February 2012, namely heating, disbudding and a combination of heating and disbudding, with untreated dormant stems as controls. Cambial reactivation and differentiation of vessel elements were monitored by light and polarized-light microscopy, and the growth of buds was followed.Key Results
Cambial reactivation and differentiation of vessel elements occurred sooner in heated seedlings than in non-heated seedlings before bud break. The combination of heating and disbudding of seedlings also resulted in earlier cambial reactivation and differentiation of first vessel elements than in non-heated seedlings. A few narrow vessel elements were formed during heating after disbudding, while many large earlywood vessel elements were formed in heated seedlings with buds.Conclusions
The results suggested that, in seedlings of the deciduous ring-porous hardwood Quercus serrata, elevated temperature was a direct trigger for cambial reactivation and differentiation of first vessel elements. Bud growth was not essential for cambial reactivation and differentiation of first vessel elements, but might be important for the continuous formation of wide vessel elements. 相似文献18.
Size dependent heat generation of magnetite nanoparticles under AC magnetic field for cancer therapy
Jun?Motoyama Toshiyuki?Hakata Ryuji?Kato Noriyuki?Yamashita Tomio?Morino Takeshi?Kobayashi Hiroyuki?Honda
Background
We have developed magnetic cationic liposomes (MCLs) that contained magnetic nanoparticles as heating mediator for applying them to local hyperthermia. The heating performance of the MCLs is significantly affected by the property of the incorporated magnetite nanoparticles. We estimated heating capacity of magnetite nanoparticles by measuring its specific absorption rate (SAR) against irradiation of the alternating magnetic field (AMF).Method
Magnetite nanoparticles which have various specific-surface-area (SSA) are dispersed in the sample tubes, subjected to various AMF and studied SAR.Result
Heat generation of magnetite particles under variable AMF conditions was summarized by the SSA. There were two maximum SAR values locally between 12 m2/g to 190 m2/g of the SSA in all ranges of applied AMF frequency and those values increased followed by the intensity of AMF power. One of the maximum values was observed at approximately 90 m2/g of the SSA particles and the other was observed at approximately 120 m2/g of the SSA particles. A boundary value of the SAR for heat generation was observed around 110 m2/g of SSA particles and the effects of the AMF power were different on both hand. Smaller SSA particles showed strong correlation of the SAR value to the intensity of the AMF power though larger SSA particles showed weaker correlation.Conclusion
Those results suggest that two maximum SAR value stand for the heating mechanism of magnetite nanoparticles represented by hysteresis loss and relaxation loss.19.
Erin Henry Luca Santini Mark A. J. Huijbregts Ana Benítez-López 《Global Ecology and Biogeography》2023,32(2):267-280
Aim
Whether intraspecific spatial patterns in body size are generalizable across species remains contentious, as well as the mechanisms underlying these patterns. Here we test several hypotheses explaining within-species body size variation in terrestrial vertebrates including the heat balance, seasonality, resource availability and water conservation hypotheses for ectotherms, and the heat conservation, heat dissipation, starvation resistance and resource availability hypotheses for endotherms.Location
Global.Time period
1970–2016.Major taxa studied
Amphibians, reptiles, birds and mammals.Methods
We collected 235,905 body size records for 2,229 species (amphibians = 36; reptiles = 81; birds = 1,545; mammals = 567) and performed a phylogenetic meta-analysis of intraspecific correlations between body size and environmental variables. We further tested whether correlations differ between migratory and non-migratory bird and mammal species, and between thermoregulating and thermoconforming ectotherms.Results
For bird species, smaller intraspecific body size was associated with higher mean and maximum temperatures and lower resource seasonality. Size–environment relationships followed a similar pattern in resident and migratory birds, but the effect of resource availability on body size was slightly positive only for non-migratory birds. For mammals, we found that intraspecific body size was smaller with lower resource availability and seasonality, with this pattern being more evident in sedentary than migratory species. No clear size–environment relationships were found for reptiles and amphibians.Main conclusions
Within-species body size variation across endotherms is explained by disparate underlying mechanisms for birds and mammals. Heat conservation (Bergmann's rule) and heat dissipation are the dominant processes explaining biogeographic intraspecific body size variation in birds, whereas in mammals, body size clines are mostly explained by the starvation resistance and resource availability hypotheses. Our findings contribute to a better understanding of the mechanisms behind species adaptations to the environment across their geographic distributions. 相似文献20.
A Maarten J Kootstra Hendrik H Beeftink Elinor L Scott Johan PM Sanders 《Biotechnology for biofuels》2009,2(1):31-14