地形对振动压路机激发地震波传播的影响

为了治理振动压路机在施工中对建筑物的影响,对振动波进行监测,通过试验数据的回归分析,得到压路机地面振动衰减规律和高差地形的振动效应。结果表明,地面振动波传播衰减规律符合负幂指数函数的形式;负高差地形会产生振动“缩小”效应;高差地形对振动波传播的影响存在距离限制。     

我国安全生产基层执法队伍建设问题与对策

通过收集分析相关统计数据和资料,深入分析我国安全生产基层执法队伍建设现状。统计分析结果表明:专门的基层执法机构仍不健全;与基层实际执法工作需要相比,执法人员相对不足;执法人员业务素质不高;执法队伍不稳定,人员变动频繁。最后从建立人员配备标准、合理调配人员、加快监察人员专业化建设进程、落实从优待安政策等4方面,提出了相应的对策。     

High salinisation risks in a typical semi-arid river network in northern China

The objective of this study was to investigate the salinisation characteristics of a semi-arid river network in northern China and highlight the influencing factors and risks. The Ziya River Basin, a typical semi-arid river network located in the North China Plain, is studied herein. Overlying water, surface sediment and riparian soil samples were collected in July and December of 2014 in the Ziya River Basin. The results showed that the average concentrations of salt content in the overlying water and surface sediment of 10 rivers in the Ziya River Basin were 1105.64 and 2159.35?mg/L, respectively. High level of salinisation was found in most rivers not only in overlying water, but also in surface sediment. The impact of the salinisation of overlying water on riparian soil diminished with distance away from the shore and had no impact beyond 15 m from the shore. Heavy pollution can contribute greatly to the salinisation of the water column and can cause significant impacts on river sediment and riparian soil. Salinisation in the overlying water affects the sediment and riparian soil, and reveals that the high risk of salinisation in the Ziya River Basin has been underestimated.     

粉尘密度对20 L球罐内粉尘分散规律影响

为分析不同粉尘因密度的差异对20 L球形爆炸装置球罐内粉尘分散过程流场变量变化和点火延迟时间的影响,利用CFD数值模拟的方法,研究了3种不同密度的粉尘在球罐分散过程中湍流动能、流场速度、粉尘浓度3种流场变量在球心处的变化规律。研究结果表明:在其他条件一致的情况下,粉尘密度越小,湍流动能的峰值越小,粉尘云浓度和流场速度的峰值则越大;粉尘密度对湍流动能的增值速率没有影响,而粉尘密度越小,流场速度和粉尘浓度的增值速率越快,粉尘浓度衰减至稳定值的时间也越短。表明粉尘密度越小,点火延迟时间也越小,因此,建议铝粉点火延迟时间在50~60 ms之间,锆粉和锌粉在60~80 ms之间。     

青岛地铁超浅埋段爆破振动监测数据特征研究

为了更好地掌握超浅隧道爆破振动规律,以青岛地铁太延区间超浅埋隧道爆破振动为例进行了研究。在地表7层建筑物各层相同位置布置测振仪对爆破振速进行实时全面监测,通过对掏槽眼、辅助眼、周边眼爆破时单段最大起爆药量与实测振速关系的回归拟合,发现此隧道的爆破振动规律并不符合一般埋深隧道适用的萨道夫斯基公式,据此提出了临空自由面影响系数,得到了萨道夫斯基计算公式的修正拟合系数。修正后的萨道夫斯基公式可更好地反映3类炮眼爆破的实际振速衰减规律,该规律可为城市地铁类似隧道的爆破施工提供参考依据。     

煤加水热化学还原反应体系H2S成生实验模拟研究

为研究煤在加水热模拟条件下H2S气体的生成规律,采用自主设计的高温高压封闭反应装置,在高温、真空条件下对煤加水反应体系进行H2S气体成生实验模拟研究。使用Agilent 7890B气相色谱对热模拟温度（250~550℃）内的气相产物取样分析。结果显示:在温度不超过300℃时,该阶段主要是发生物理脱吸附作用,且化学还原作用还较微弱,H2S气体生成量较少;在300~550℃,该阶段为煤中有机硫分解释放硫自由基的主要阶段,H2S气体生成量急剧攀升,在450℃达到最大值。总体来说,煤中有机硫分解释放的硫自由基量对H2S气体的生成量有重要的影响,硫自由基量越高,H2S的生成量就越大。     

Tween-20胶束溶液对甲苯的增溶吸收作用规律及预测

以Tween-20非离子表面活性剂及助表面活性剂混合溶液作为吸收剂,增溶吸收甲苯有机废气,根据增溶实验测定的表观亨利系数预测甲苯吸收容量,结果表明,当表面活性剂浓度大于临界胶束浓度(CMC)时增溶吸收效果显著,溶质的表观溶解度与表面活性剂浓度呈正比关系;助表面活性剂可以不同程度的提高表面活性剂溶液的增溶能力,其规律为正丁胺>正丁醇>正丁酸;利用表观亨利系数预测吸收剂吸收容量的平均相对偏差分别为7.34%和8.85%,预测方法可行.     

玛纳斯河水质参数时空变化规律浅析

玛纳斯河近5年水质监测结果统计分析表明,玛纳斯河水质良好,平常各监测项目均不超标。在汛期,因泥沙及有机质的影响,SS超标,高锰酸盐指数也有部分超标。上述2参数年际变化亦较大,且有逐年上升趋势。     

A PARTICIPATORY APPROACH TO WATERSHED MANAGEMENT: THE BRAZILIAN SYSTEM1

ABSTRACT: Brazil is currently facing the challenge of implementing a new water resources management system to promote the rational and sustainable use of the country's waters. This system is based on the following principles of water management: (2) stakeholders' participation; (2) the watershed as the planning and management unit; and (3) the economic value of water. Stakeholders' participation and the involvement of civil society in the decision making process is guaranteed by permanent seats in the watersheds' management committees. These committees are the highest decision level for the establishment of water policy and for planning its use. The executive branch of the committees is the watershed agency or the water agency. This paper presents the recently approved Brazilian water resources management system and discusses the participatory approach followed to validate and to ensure prompt response to decisions regarding water use by all stakeholders. The formulation of the National Water Law (January/1998) was also supported by extensive consultation with civil society, professional associations, state and municipal governments as well as with federal governmental agencies and private sector organizations. It also presents an overview of the formulation of the National Water Law. Finally, as watershed committees have been created and are already operating in a limited number of watersheds, some of the major obstacles to the success of the new system are discussed along with alternatives for overcoming such obstacles.