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1.
A pilot study was performed to investigate whether the application of a new mechanical ventilation system with a fine F8 (MERV14) filter could improve indoor air quality in a high school near the Amsterdam ring road. PM10, PM2.5, and black carbon (BC) concentrations were measured continuously inside an occupied intervention classroom and outside the school during three sampling periods in the winter of 2013/2014. Initially, 3 weeks of baseline measurements were performed, with the existing ventilation system and normal ventilation habits. Next, an intervention study was performed. A new ventilation system was installed in the classroom, and measurements were performed during 8 school weeks, in alternating 2‐week periods with and without the filter in the ventilation system under otherwise identical ventilation conditions. Indoor/outdoor ratios measured during the weeks with filter were compared with those measured without filter to evaluate the ability of the F8 filter to improve indoor air quality. During teaching hours, the filter reduced BC exposure by, on average, 36%. For PM10 and PM2.5, a reduction of 34% and 30% was found, respectively. This implies that application of a fine filter can reduce the exposure of schoolchildren to traffic exhaust at hot spot locations by about one‐third.  相似文献   
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There are currently no epidemiological studies on health effects of long-term exposure to ultrafine particles (UFP), largely because data on spatial exposure contrasts for UFP is lacking. The objective of this study was to develop a land use regression (LUR) model for UFP in the city of Amsterdam. Total particle number concentrations (PNC), PM10, PM2.5, and its soot content were measured directly outside 50 homes spread over the city of Amsterdam. Each home was measured during one week. Continuous measurements at a central urban background site were used to adjust the average concentration for temporal variation. Predictor variables (traffic, address density, land use) were obtained using geographic information systems. A model including the product of traffic intensity and the inverse distance to the nearest road squared, address density, and location near the port explained 67% of the variability in measured PNC. LUR models for PM2.5, soot, and coarse particles (PM10, PM2.5) explained 57%, 76%, and 37% of the variability in measured concentrations. Predictions from the PNC model correlated highly with predictions from LUR models for PM2.5, soot, and coarse particles. A LUR model for PNC has been developed, with similar validity as previous models for more commonly measured pollutants.  相似文献   
3.
There is ample evidence suggesting (e.g., A. Tesser & S. Rosen, 1975) that people are reluctant to transmit bad news. Research on rumors, on the other hand, suggests that people sometimes are less reluctant to transmit bad news. It is argued that differences between the 2 lines of research include the definitiveness of the consequences of the news and the relationship between communicator and recipient. The influence of these 2 factors on news transmission was investigated in 3 experiments. Results showed that bad news with indefinite consequences was transmitted more often than bad news with definite consequences and that both kinds of bad news were transmitted more often if the recipient was a friend rather than a stranger. Differences in feelings of moral responsibility to transmit the news largely accounted for both effects. The 2 factors did not affect the likelihood of good news transmission. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Antistasin is a Factor Xa inhibitor that is present in the salivary glands of the Mexican leech Haementeria officinalis. The antistasin protein consists of 119 amino acids, of which residues 1-55 (domain I) are 56% similar to residues 56-110 (domain II). Of the nine C-terminal amino acids (residues 111-119; domain III), four are positively charged. The reactive site for Factor Xa is located in domain I. In this study we assessed the role of separate domains and of individual amino acids in the reactive site for the inhibition of Factor Xa. A series of mutants was constructed and expressed in Chinese hamster ovary (CHO) cells. In vitro chromogenic assays for Factor Xa show that domain I is sufficient for inhibition of Factor Xa. Domains II and III neither contain any intrinsic Factor Xa inhibitory activity, nor contribute to the activity of domain I. Furthermore, domain II does not become a Factor Xa inhibitor by partially adaptating its sequence towards that of the reactive site in domain I. Mutation of the cysteine at position 33 is not crucial for Factor Xa inhibition, suggesting a relatively rigid reactive site loop structure.  相似文献   
6.
OBJECTIVE: To determine the effect of adequate scientific research on the treatment of extracranial stenosis of the internal carotid artery. DESIGN: Retrospective and comparative. SETTING: Twenty Medical Spectrum, Enschede, the Netherlands. METHOD: A comparison was made of the relevant data from 2 years of carotid artery surgery before (1989-1990; period I) and after the publication of two randomized multicentre studies (1994-1995; period II). RESULTS: The number of patients treated surgically and the number of carotid artery desobstructions had increased during period II by 339% and 319%, respectively. In period I, 25% of the patients had an asymptomatic ipsilateral stenosis of the internal carotid artery; in period II, this had decreased to 11%. In period I, 65% of the patients had a stenosis in excess of 70% of the diameter of the vessel; in period II this was 85%. The combined mortality and permanent disabling morbidity after 30 days was 6% in period I and 3% in period II. CONCLUSION: After the publication of two high-quality studies in 1991, the number of carotid artery operations increased by over 300%. The indications for the surgical treatment of stenosis were stricter rather than less strict in period II. The increase of the number of carotid desobstructions can be explained by the fact that GPs' and neurologists' referral to the vascular surgeon has changed. This change in the referring pattern may be the consequences of use of 'evidence-based' medicine.  相似文献   
7.
I''Park城     
I'Park城是专门为特定人群设计的一个很独特的地方。此项目的优势在于其丰富,多层次的空间,使得建筑和景观能够统一起来,达到非常和谐的境界。I'Park城的设计灵感来自于回家:通过一系列独特经验创造空间的和谐性;一场独特的归家之旅。  相似文献   
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In the past 30 years, staging and treatment of Hodgkin's disease have changed dramatically, and prolonged remission can now be induced in the majority of patients. Our purpose was to assess improvement in long-term survival, previously reported for specific patient groups, among unselected patients diagnosed and treated between 1972 and 1993 in general hospitals in South-East Netherlands. Data on all 345 Hodgkin's patients were derived from the population-based Eindhoven Cancer Registry; histopathology and clinical records were reviewed. Follow-up was attained up to 1994. Relative survival rates, i.e. the ratio of observed to expected rates, were 80% after 5, 70% after 10 and 67% after 15 years. Independent prognostic factors for lower overall survival were (in decreasing order of significance): advanced age, histology (lymphocyte depletion), advanced stage and earlier period of diagnosis. Distribution of age and stage did not change over the study period, but there was a modest increase in the incidence of the nodular sclerosis histological subtype. Crude 5-year survival rates improved from 60% in the period 1972-1976 to 81% in the period of 1987-1992 (P < 0.005). The largest improvement occurred in the 1970s and was most prominent among those aged over 50 years. As previously reported, cured Hodgkin's patients exhibit a higher mortality rate, which can be explained by treatment-related long-term complications such as second malignancies and cardiovascular diseases. The relatively high survival rates compared to other population-based studies may be attributable to the existence of a regional network within the framework of a comprehensive cancer centre. Better staging, new combinations of chemotherapy, improved radiation technology, advances in supportive care as well as more frequent intensive treatment of the elderly could explain the improvement in prognosis.  相似文献   
10.
The Monitored Drift Tubes (MDTs) of the ATLAS Muon Spectrometer have been paired to form so-called twin-tubes to measure the coordinate which runs along the wire direction. This modification endows the MDTs with full 3D track reconstruction using specially designed electronic boards. The performance of the twin-tubes has been measured for an equipped MDT chamber at the ATLAS Muon Cosmic Ray Test Stand at NIKHEF. The efficiency of a twin-tube has been determined to be 99.8%, and the measured resolution 17 cm per hit. By equipping one multilayer consisting of three layers and combining the measurements a resolution of 10 cm has been obtained.  相似文献   
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