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11.
Investigations of Ce3+-doped Cs2LiLaBr6 (CLLB) crystals show a systematic trend in their scintillation properties with varying Ce concentrations. The concentration studies provide input in the optimization of growth of the CLLB crystals. Scintillation properties viz. radioluminescence, energy resolution, light yield, decay times, and non-proportionality are discussed for samples from 0% to 20% Ce concentration.  相似文献   
12.
At present, ceiling-mounted diffusers are very popular for indoor air distribution, particularly in offices, owing to greater efficiency in the distribution of the air supply and a more comfortable indoor environment. The objective of this study is to construct an effective model to design the indoor airflow of an attached plane jet after its impingement with the corner in a room. In this study, a full-scale test facility was set up to obtain detailed experimental data. One commercial CFD tool, CFX 11.0, was used to simulate the air velocity distribution of an attached plane air jet bounded by the ceiling and an insulated wall. One semi-empirical model was also constructed to predict the impingement jet velocity. The results show that bout the semi-empirical model and CFX 11.0 were able to predict the maximum velocity of an impinging jet at low Reynolds numbers, 1000 and 2000, with an inaccuracy of ±11%. However, the semi-empirical model could be more conveniently used to predict the maximum jet velocity decay after its impingement the corner in a room than CFD simulation in terms of accuracy and the time required to design the indoor airflow pattern.  相似文献   
13.
Interest in finding out passive ways to keep the variation in the indoor climate within the comfort zone is gaining in popularity. One possible solution is the use of the moisture-buffering property of materials. In this study, the effects of the ventilation system and moisture-buffering properties of the building fabric on the stability of the indoor temperature and humidity are analysed by means of long-term field measurements. Indoor climate measurements were carried out in 170 detached houses (248 rooms). Temperature and relative humidity were measured continuously in bedrooms and living rooms at one-hour intervals over a one-year period. In general, it may be concluded that in this study, the ventilation had a greater effect on the indoor climate than the properties of the building fabric. The dampening effect of hygroscopic materials was remarkably less in the field measurements than it was in simulations in different studies. This indicates that completely non-hygroscopic and fully hygroscopic houses do not exist in reality. The hygroscopic mass of furniture, textiles, etc. is probably a factor that plays a significant role in indoor humidity, as do real air change rates, including window airing. Simulation tools need to be modified in order to be able also to handle furniture, textiles, and books, etc.  相似文献   
14.
Space heating load is decreasing in modern Finnish apartments due to lower U-values of the construction, tight envelopes and heat recovery from exhaust ventilation air. This makes it possible to develop a new combined low temperature water heating system with nominal supply/return water temperatures of 45 °C/35 °C. Such a system includes radiators in rooms and floor heating in bathrooms.In this study, the performance of an apartment building is determined by using dynamic simulation. The simulation results for the combined low temperature water heating system are compared with those for three conventional radiator and floor heating systems. The results show that the combined low temperature water heating system performs well and is able to maintain the zones within the required temperature levels. The thermal comfort analysis indicates that the drifts and ramps in operative temperature using the four studied heating systems are within the limits of Ashrae Standard 55-2004.Temperature measurements in a test room are carried out to find the vertical difference of air temperature using two methods: radiator heating and floor heating. These measurements indicate that there is only a small vertical temperature difference that would not produce any significant thermal discomfort.  相似文献   
15.
Degrading 2‐ethylhexyl‐containing PVC floorings (eg DEHP‐PVC floorings) and adhesives emit 2‐ethylhexanol (2‐EH) in the indoor air. The danger of flooring degradation comes from exposing occupants to harmful phthalates plasticisers (eg DEHP), but not from 2‐EH as such. Since the EU banned the use of phthalates in sensitive applications, the market is shifting to use DEHP‐free and alternative types of plasticisers in PVC products. However, data on emissions from DEHP‐free PVC floorings are scarce. This study aimed at assessing the surface and bulk emissions of two DEHP‐free PVC floorings over three years. The floorings were glued on the screed layer of concrete casts at 75%, 85%, and 95% RH. The volatile organic compounds (VOCs) were actively sampled using FLEC (surface emissions) and micro‐chamber/thermal extractor (µ‐CTE, bulk emissions) onto Tenax TA adsorbents and analyzed with TD‐GC‐MS. 2‐EH, C9‐alcohols, and total volatile organic compound (TVOC) emissions are reported. Emissions at 75% and 85% RH were similar. As expected, the highest emissions occurred at 95% RH. 2‐EH emissions originated from the adhesive. Because the two DEHP‐free floorings tested emitted C9‐alcohols at all tested RH, it makes the detection of flooring degradation harder, particularly if the adhesive used does not emit 2‐EH.  相似文献   
16.
Colorectal cancer (CRC) is one of the most common malignancy and cause of cancer death worldwide, and it still remains a therapeutic challenge for western medicine. There is strong evidence that, in addition to genetic predispositions, environmental factors have also a substantial impact in CRC development. The risk of CRC is attributed, among others to dietary habits, alcohol consumption, whereas physical activity, food containing dietary fiber, dairy products, and calcium supplements have a protective effect. Despite progress in the available therapies, surgery remains a basic treatment option for CRC. Implementation of additional methods of treatment such as chemo- and/or targeted immunotherapy, improved survival rates, however, the results are still far from satisfactory. One of the reasons may be the lack of deeper understanding of the interactions between the tumor and different types of cells, including tumor infiltrating granulocytes. While the role of neutrophils is quite well explored in many cancers, role of eosinophils and basophils is often underestimated. As part of this review, we focused on the function of different granulocyte subsets in CRC, emphasizing the beneficial role of eosinophils and basophils, as well as dichotomic mode of neutrophils action. In addition, we addressed the current knowledge on cells of granulocyte origin, specifically granulocytic myeloid derived suppressor cells (Gr-MDSCs) and their role in development and progression of CRC.  相似文献   
17.
Journal of Porous Materials - Two mesoporous silica materials: MCM-41 and SBA-15 were applied as potential nanocarriers for poorly soluble drug—nimodipine. Drug incorporation was performed...  相似文献   
18.
The aim of the worksite study is to elucidate the strain reducing impact of different forms of spending lunch breaks. With the help of the so-called silent room cabin concept, it was possible to induce a lunch-break relaxation opportunity that provided visual and territorial privacy. To evaluate the proposed effects, 14 call center agents were assigned to either 20 min progressive muscle relaxation (PMR) or small-talk (ST) break groups. We analyzed the data in a controlled trial for a period of 6 months (every 2 months four measurements a day at 12:00, 13:00, 16:00, 20:00) using independent observer and self-report ratings of emotional, mental, motivational, and physical strain. Results indicated that only the PMR break reduced postlunchtime and afternoon strain. Although further intervention research is required, our results suggest that PMR lunch break may sustainable reduce strain states in real worksite settings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
19.
Environmental influences, especially temperatures below the freezing point, can affect the performance and long-term stability of PEMFCs. Within the scope of this research, a completely new test procedure was developed to characterize PEMFC single cells with respect to their long-term stability at temperature cycles between 80 °C and ?10 °C. Using this procedure, the behavior of PEMFC single cells (active surface area of 43.6 cm2) with different cathode-ionomer-to-carbon (I/C) weight ratios (0.5/1.0/1.5) was evaluated. The generated in-situ measurement data clearly demonstrate that the performance of each PEMFC single cell changes individually as a function of the cathode I/C-ratio during the 120 stress cycles. While the MEA with an I/C ratio of 0.5 showed a power loss of ~1.49%, the MEAs with an I/C ratio of 1.0 and 1.5 showed a power loss of about ~7.75% and ~24.7%, respectively. The subsequent post-mortem ex-situ analyses clearly showed how the test procedure and the different I/C-ratios affected the changes in the catalyst layers (CL). The destructive mechanisms responsible for the changes can be divided into two categories: One part was driven by rapid enthalpy change leading to mechanical failure, and the other part, which led to the reduction of cathode CL thickness, was driven by rapid potential changes and potential shifts (overpotentials). This reduction in cathode CL thickness ultimately leads to an accumulation and excessive load of ionomer in the direction of GDL, resulting in a reduction in pore size, a shift in the core reaction area, and high O2 transport resistance.  相似文献   
20.
OBJECTIVE: To prospectively assess the efficacy of intramuscular (i.m.) triamcinolone acetonide in the treatment of pseudogout. METHODS: Fourteen patients with crystal proven pseudogout presenting with an acute attack within 5 days of onset were treated with intramuscular triamcinolone acetonide 60 mg and followed for 30 days. Patients with inadequate response were eligible for a 2nd triamcinolone acetonide injection on Day 1-2. RESULTS: Twelve patients had contraindication to nonsteroidal antiinflammatory agents (NSAID). Acute arthritis was monoarticular in 10 patients, and involved 2 or more joints in 4 patients. All patients had good clinical response to triamcinolone acetonide based on restoration of near baseline joint range of motion and joint circumference, and at least 50% improvement in patient and physician global assessment. Major clinical improvement occurred by Day 1-2 (2 patients), Day 3-4 (11 patients), and Day 10-14 (one patient). Six patients required a 2nd triamcinolone acetonide injection on Day 1-2. Toxicities were not observed. CONCLUSION: I.m. triamcinolone acetonide appears to be safe, well tolerated, and effective in the treatment of pseudogout. It may be a reasonable alternative therapy when NSAID are contraindicated, and for polyarticular attacks where intraarticular corticosteroids are impractical.  相似文献   
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