从刻蚀电路板废液中制取硫酸铜的工艺研究

研究了以刻蚀电路板废液为原料制取硫酸铜的工艺条件。探讨了Fe3 的干扰,不同的pH以及不同浓度的NaOH和H2SO4对产品质量的影响。结果表明:采用15%~20%NaOH与20%H2SO4可使产品的回收率达92%,产品纯度可达98%。     

俄罗斯退休养老金

养老问题是目前全球性的问题,一方面人口老龄化的压力愈发沉重,另一方面养老成本明显提高,在众多国家面对如此棘手问题的时候,俄罗斯联邦却做得举国上下称赞,很值得我们借鉴。     

国际金融危机下教育扩张的历史经验与启示

当前国际金融危机对我国教育发展造成了强烈的冲击,同时又带来教育发展的难得机遇。基于经验和事实提出了我国未来教育规模扩张的理论预期,但金融危机下的教育扩张面临教育财政、办学条件和毕业生就业等严重压力。西方国家在历次金融危机中积累了丰富的经验,也有些严重的教训,为我国中长期教育改革和发展提供了一些有益的启示。     

金融危机的观察:以风险与法为视角

过于关注危机监管的法律人忘记了一点,在认识论意义上,对危机的观察都预设了某种区分,区分不同,观察结论各异,因而危机应对之法也有差别。以危机／风险之区分为出发点来观察金融市场,可发现危机的不可避免性和监管的滞后性。这不仅源于危机的风险本质,还在于基于风险／安全、风险／效益和风险／文化的不同观察图式来审视金融风险,亦可能带来危机对策法上的冲突与对立,因而在治理上很难达成共识。尤值得关注的是,只有在风险／文化这一区分指引下,法律人才有可能增进在中国语境中的危机观察能力,找到契合“本土资源”的危机应对策略,而不为美国主流意识形态话语所支配。     

从政府危机管理反思行政伦理

近年来我国公共危机事件频发,严重威胁人类安全和社会稳定,给政府危机管理带来新的挑战。危机管理是一项非常规化的情景性管理,极大地考验着政府的随机决策和执行能力,同时对行政伦理也提出了新的要求。文章试从行政伦理的角度阐述政府危机管理,在略述危机管理中的行政伦理困境后,阐述了走出政府危机管理行政伦理困境的建议,有助于公共危机管理的人性化解决。     

新型城镇化面临的城乡社会危机及其规划策略

当前我国快速城镇化斜率陡悬,压缩了城乡问题释放和缓解的时间,从而快速积聚城乡社会危机。现阶段我国城乡社会危机的焦点分布在特大城市和农村地区两端。我国新型城镇化的总体策略,既要把握好全局的平衡发展,又要着重针对特大城市和广大农村地区两端潜在的社会危机,制定相应的对策。缓解特大城市社会危机的规划策略重点包括:大力推进城市基本公共设施和服务均等化,确保低收入家庭的住房供给"托底",保障老龄化社会为老服务的基本条件,并通过城市社区规划寻求特大城市的社会管理改革与创新;广大农村地区社会危机的规划策略重点包括:注重乡村产业经济"造血机能"的培育,大力推进乡村社会自治,鼓励地方文化保护并加强地方传统特色文化传承,通过促进农村社区规划来探索乡村社会管理改革与创新。     

The effects of a calf pump device on second half performance of a simulated soccer match in competitive youth players

During soccer matches, performance decrements have been reported that relate to both physical abilities and technical skills. To investigate the effects of low-frequency electrical stimulation LFES (VeinoplusSport®, Ad Rem Technology, France) administered during half-time recovery on performance alterations during the second half. Twenty-two highly trained young players undertook a soccer-match simulation (SAFT⁹⁰). During half-time, they were randomly assigned to LFES group or Placebo group. Each half was split into 3 bouts of 12 minutes. Following each bout, maximal strike speed (MSS), sprint test (ST), maximal sprint accelerations (MA) and metabolic power (MP) were determined in both groups. Arterial (AF) and venous flows (VF) were measured at rest and at the end of half-time. LEFS group exhibited beneficial effects on performance compared to the Placebo group with a likely effect for MSS, ST, MA, and a possible effect for MP. AF and VF increased statistically more in LEFS group compared to Placebo group. The use of specific calf-pump LFES during half-time of a youth simulated soccer match attenuated the decrease in performance during the second half compared to Placebo group. This effect is most marked at the beginning of the second half with regards to explosive parameters.     

Evening electronic device use and sleep patterns in athletes

The present study aimed to investigate pre-sleep behaviours (including evening electronic device use) and sleep quantity in well-trained athletes. Seventy well-trained athletes (44 females, 26 males) aged 21 ± 4 y from a range of team and individual sports were asked to complete an online sleep diary for 7 days. The sleep diary included questions about pre-sleep behaviours (e.g. napping, caffeine intake), electronic device use in the 2 h prior to bedtime (e.g. type of device and duration of use) and sleep (e.g. time in bed, sleep onset latency). On average, athletes spent 8:20 ± 1:21 h in bed each night. Associations between age, time in bed and sleepiness suggested that younger athletes spent more time in bed (B = -0.05, p = 0.001) but felt sleepier (r = -0.32, p < 0.01) than older athletes. On average, athletes mostly used electronic devices for 0–30 min prior to sleep. The use of multiple devices in the evening was associated with more perceived difficulty in falling asleep (B = 0.22, p = 0.03), but no associations existed with other sleep variables. In summary, younger athletes may require later start times or improved sleep quality to resolve excessive sleepiness.     

厌氧氨氧化菌活性的快速恢复及运行

为研究厌氧氨氧化(anaerobic ammonium oxidizing,ANAMMOX)菌的活性恢复,采用SBR工艺对长时间(100 d左右)停止运行的反应器中ANAMMOX菌进行活性培养。经过22 d的恢复试验,ANAMMOX菌活性基本恢复,在第17天,NH+4—N和NO-2—N的转化率均在90%以上,TN的去除率在80%以上。在培养过程中,载体的颜色由白色逐渐变成淡黄色。结果表明,在常温闲置较长时间的反应器中ANAMMOX菌的活性可恢复性强,恢复周期短,恢复后的脱氮性能良好;ANAMMOX反应器通过对生物膜载体的培养可以使ANAMMOX菌的活性快速恢复。     

Sand training: Exercise-induced muscle damage and inflammatory responses to matched-intensity exercise

This study compared markers of muscle damage and inflammation elevated by a matched-intensity interval running session on soft sand and grass surfaces. In a counterbalanced, repeated-measures and crossover design, 10 well-trained female athletes completed 2 interval-based running sessions 1 week apart on either a grass or a sand surface. Exercise heart rate (HR) was fixed at 83–88% of HR maximum. Venous blood samples were collected pre-, post- and 24?h post-exercise, and analysed for myoglobin (Mb) and C-reactive protein (CRP). Perceptual ratings of exertion (RPE) and muscle soreness (DOMS) were recorded immediately post- and 24?h post-exercise. A significant time effect showed that Mb increased from pre- to post-exercise on grass (p?=?.008) but not on sand (p?=?.611). Furthermore, there was a greater relative increase in Mb on grass compared with that on sand (p?=?.026). No differences in CRP were reported between surfaces (p?>?.05). The HR, RPE and DOMS scores were not significantly different between conditions (p > .05). These results suggest that in response to a matched-intensity exercise bout, markers of post-exercise muscle damage may be reduced by running on softer ground surfaces. Such training strategy may be used to minimize musculoskeletal strain while still incurring an equivalent cardiovascular training stimulus.