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41.
溶剂热法合成SnWO4及其可见光催化活性   总被引:1,自引:1,他引:0  
采用溶剂热法合成了新型的可见光催化剂SnWO4,以甲基橙为目标污染物,考察了合成温度、合成时间和煅烧工艺对催化剂可见光催化活性的影响。实验结果表明:煅烧工艺会明显降低催化剂的光催化活性;在合成温度为180℃、合成时间为8h、未煅烧的条件下,合成的催化剂的光催化效果最好,光照90min后,对甲基橙的降解率可达99.93%。  相似文献   
42.
超临界水氧化法处理造纸黑液   总被引:1,自引:1,他引:0  
采用自制的超临界水氧化反应装置,对造纸工业排放的黑液进行处理。考察了反应温度、反应压力、反应时间、过氧量(初始反应时所加氧气的量与废水完全氧化所需氧气的理论量的比,%)等对黑液中COD去除率的影响。实验结果表明,处理黑液的最佳反应条件为:反应温度500℃,压力26M Pa,过氧量500%,反应时间120s。在此最佳条件下处理COD为85 000m g/L的造纸黑液,COD去除率可达99.9%。  相似文献   
43.
化工园区空气中非甲烷总烃与挥发性有机物的定量关系   总被引:1,自引:0,他引:1  
采用美国环保署(EPA)推荐的TO14/15方法和自动监测测定了某化工园区空气中挥发性有机物(VOC)以及非甲烷总烃,测定结果显示化工园区空气中非甲烷总烃与VOC的定量关系可以通过有效碳质量浓度建立,即非甲烷总烃有效碳质量浓度和VOC有效碳质量浓度之和相等。并藉此定义总有效碳解析度(R)以表征空气自动监测选定项目对空气有机污染的覆盖率指标,计算结果表明该空气自动监测选定的11项指标平均可表征该区域空气有机污染的71%。  相似文献   
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To understand how trust in supervisor translates into individual job performance, we hypothesize that trust in supervisor facilitates positive psychological conditions of meaningfulness, safety, and availability, which in turn predict individual job performance. We assert that each of the three mediating paths in our model represents a distinct mechanism by which trust in supervisor contributes to individual job performance. We test our hypotheses with 206 supervisor–subordinate dyads and find that trust in supervisor contributes to job performance through psychological availability and psychological safety but not psychological meaningfulness. By examining three different psychological mechanisms within the same frame, we provide a test that compares and contrasts the uniqueness of the three pathways. Our findings suggest practical ways for managers to build trust with subordinates and guidance for the design of productive work conditions. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
47.
Research on micropore mufflers was started in the middle of the 1970s. In this article we have summarized and systematized what has been done in the past 20 years. Some expressions, derivations, and calculation curves have been formally modified to make them easier to understand and apply. Some new considerations have been added. The main purpose of this article is to introduce the fundamentals, theories, and calculations that are useful for the design of a micropore muffler. Therefore, we have not included any experiments. Direct and indirect experimental proofs can be found in the given relevant references. Micropore mufflers are grouped into two classes, simple micropore mufflers and expansion micropore mufflers. The latter have additional noise reduction due to flow expansion. Noise reduction and flow are two important aspects that have been discussed in detail.  相似文献   
48.
Different from walking, ladder climbing requires four-limb coordination and more energy exertion for below-knee amputees (BKAs). We hypothesized that functional deficiency of a disabled limb shall be compensated by the other three intact limbs, showing an asymmetry pattern among limbs. Hand and foot forces of six below-knee amputees and six able-bodied people were collected. Hand, foot and hand/foot sum force variances between groups (non-BKA, intact side and prosthetic side) were carefully examined. Our hypothesis was validated that there is asymmetry between prosthetic and intact side. Results further showed that the ipsilateral hand of the prosthetic leg is stronger than the hand on the intact side, compensating weakness of the prosthetic leg. Effects of ladder rung separations and ladder slant on asymmetric force distribution of BKAs were evaluated, indicating that rung separation has a more significant interactive effect on hand/foot force of BKAs than ladder slant.  相似文献   
49.
Objectives. The aim of this article is to reduce the risk of occupational hazards and improve safety conditions by enhancing hazard knowledge and identification as well as improving safety behavior for freight port enterprises. Methods. In the article, occupational hazards to health and their prevention measures of freight port enterprises have been summarized through a lot of occupational health evaluation work, experience and understanding. Results. Workers of freight port enterprises confront an equally wide variety of chemical, physical and psychological hazards in production technology, production environment and the course of labor. Such health hazards have been identified, the risks evaluated, the dangers to health notified and effective prevention measures which should be put in place to ensure the health of the port workers summarized. Discussion. There is still a long way to go for the freight port enterprises to prevent and control the occupational hazards. Except for occupational hazards and their prevention measures, other factors that influence the health of port workers should also be paid attention to, such as age, work history, gender, contraindication and even the occurrence and development rules of occupational hazards in current production conditions.  相似文献   
50.
Effects of work boots and load carriage (6.4?kg and 12.8?kg) on gait pattern were investigated. The protective work boots were examined by comparison with running shoes through human performance tests with 15 male participants. The loads were carried symmetrically and asymmetrically on the shoulder and hand. Statistical data analysis showed a prolonged stance phase and decreased double support for work boots. A significantly increased ground reaction force was found in work boot conditions as the weight of loads increases. This study demonstrates that inflexible and heavy work boots restrict foot movement and require greater torque at the ankle to propel the body forward, which may increase physical strain and the risk of musculoskeletal injuries. Development of improved fixation methods for work boots, increased use of flexible protective layers and further study of anthropometry of human foot morphology for improved safety and work efficiency of industry workers are suggested.  相似文献   
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