1株耐油甲醛降解菌的分离鉴定及降解特性

烹饪油烟的健康危害一直以来受到广泛关注.以甲醛为代表的醛类污染物是烹饪油烟排放的主要污染物之一.微生物法降解甲醛具有工艺简单、成本低及无污染等优点.本研究从烹饪油烟冷凝液中分离筛选出1株具有甲醛降解能力的菌株XF-1,经序列鉴定结合菌落形态特征及生理生化试验,该菌株被鉴定为解淀粉芽孢杆菌(Bacillus amyloliquefaciens sp.).该菌株具有能耐受高油环境的性能,最大耐受浓度为900 g·L^-1.在甲醛浓度为100 mg·L^-1的培养基中,菌株XF-1在34 h内的甲醛降解率为95.80%;当甲醛初始浓度<300 mg·L^-1时,菌株XF-1能够在120 h以内完全降解溶液中的甲醛;甲醛浓度为800mg·L^-1时,在96 h,菌株XF-1的降解率达到73.01%,并可耐受1.5 g·L^-1浓度的甲醛.通过单因素(p H、接种量、甲醛浓度和温度)试验,得到该菌株最佳生长温度为30℃、最佳生长pH为6左右,最佳接种量为10%.利用GC-TOF-MS进一步分...     

河北省火电企业吨煤烟气排放量测定及污染动态预测

火电企业大气污染动态预测是大气污染控制的基础。采用现场实测法,对河北省36家火电企业101台机组锅炉进行现场监测,经统计分析给出不同装机容量吨煤烟气排放量,并与其他方法进行了比较,发现实测结果更为合理。在此基础上,建立吨煤SO₂、NO_x,烟尘排放量和烟气浓度的关系,为火电企业大气污染动态预测提供新的公式,对定量测定火电企业污染物排放提供参考。     

Kinetic mechanism and effects of molecular structure on thermal hazards of azo compounds

In this paper, the kinetic mechanism of AIBN, AMBN, and ABVN was proposed, and the effect of molecular structure on their thermal hazards based on the kinetic mechanism was investigated. Calculated by non-isothermal DSC datum, the kinetic mechanism of AIBN, AMBN, and ABVN is revealed by the linear relationship between the integrated form of mechanical function and reaction time. The results indicate that the thermal decomposition process is controlled by the Johnson-Mehl-Avrami equation. Based on the determination of kinetic mechanism function, the reaction rate constants at various heating rates are directly calculated, and the intercept of the best fitting straight line of reaction rate constants with heating rate is approximately equal to the reaction rate constant under isothermal conditions. Besides, theoretical values obtained by multiplying kinetic mechanism function by reaction rate are well consistent with the experimental values, suggesting that the kinetic mechanism obtained is credible. Bond Dissociation Energies (BDE) calculated by quantum chemical equations are employed to evaluate the thermodynamics stability of AIBN, AMBN, and ABVN. Depending on similar molecular structures, the influence of differentiated group structure on the thermodynamic stability represented by BDE and heat release and the kinetic stability characterized by reaction rate constant were revealed. Finally, the results demonstrate that the thermal hazard increases as the volume of substituent group and molecular weight.     

Effects of age and sex ratios on offspring recruitment rates in translocated black rhinoceros

Success of animal translocations depends on improving postrelease demographic rates toward establishment and subsequent growth of released populations. Short‐term metrics for evaluating translocation success and its drivers, like postrelease survival and fecundity, are unlikely to represent longer‐term outcomes. We used information theory to investigate 25 years of data on black rhinoceros (Diceros bicornis) translocations. We used the offspring recruitment rate (ORR) of translocated females—a metric integrating survival, fecundity, and offspring recruitment at sexual maturity—to detect determinants of success. Our unambiguously best model (AICω = 0.986) predicted that ORR increases with female age at release as a function of lower postrelease adult rhinoceros sex ratio (males:females). Delay of first postrelease reproduction and failure of some females to recruit any calves to sexual maturity most influenced the pattern of ORRs, and the leading causes of recruitment failure were postrelease female death (23% of all females) and failure to calve (24% of surviving females). We recommend translocating older females (≥6 years old) because they do not exhibit the reproductive delay and low ORRs of juveniles (<4 years old) or the higher rates of recruitment failure of juveniles and young adults (4–5.9 years old). Where translocation of juveniles is necessary, they should be released into female‐biased populations, where they have higher ORRs. Our study offers the unique advantage of a long‐term analysis across a large number of replicate populations—a science‐by‐management experiment as a proxy for a manipulative experiment, and a rare opportunity, particularly for a large, critically endangered taxon such as the black rhinoceros. Our findings differ from previous recommendations, reinforce the importance of long‐term data sets and comprehensive metrics of translocation success, and suggest attention be shifted from ecological to social constraints on population growth and species recovery, particularly when translocating species with polygynous breeding systems.     

不同冲击速度下硬煤的力学特性试验研究

为了研究硬煤破坏过程中的动态力学特性，采用Φ50 mm变截面分离式霍普金森压杆（SHPB）试验系统，对45#钢制薄壁套筒施加环向约束的硬煤试件进行不同加载速率的冲击压缩试验，得到被动围压下轴向应力-应变曲线、径向应力-应变曲线及最大被动围压和冲击速度的关系。研究结果表明:峰值应力、峰值应变随着冲击速度的增大而增大，最大被动围压值与冲击速度呈幂次增长的关系；被动围压下的硬煤试件变形受到限制，试件延性、抗压能力显著提高；随着冲击速度的增大，薄壁套筒对试件的约束也逐渐增大，达到峰值后，冲击速度对被动围压的影响减小，筒壁厚度影响着被动围压效果。     

我国公众参与环境决策的运行机制及其优化

本文简要论述了良好的决策机制是公众参与环境决策的基本保障,分析了当前我国公众参与环境决策运行机制存在的不足,并提出了优化其运行机制的一些思路。     

构建农民收入增长的长效机制

“三农问题”是关系国家经济和社会发展全局的问题，其核心是农民收入增长，农民收入增长的关键是构建收入增长的长效机制。本文通过分析中国农民收入的现状，从制度视角分析农民收入增长缓慢的土地制度、税费制度、金融体制、公共品供给体制以硬社会保障制度等方面原因．在此基础上提出构建中国农民收入增长长效机制的制度框架。     

WATER-SURFACE PROFILES WITHOUT ENERGY LOSS COEFFICIENTS1

ABSTRACT: This paper describes a new method of computing water-surface profiles, which does not require the assumption of hydrostatic pressure or of roughness coefficients. The method is based upon distributing entropy production values along a channel as uniformly as boundary conditions permit. The method requires a discharge capacity rating at a channel cross-section within the limits of the reach of the channel. A new theoretical relationship between the kinetic and momentum coefficients for the velocity profile is used, together with a dynamic programming technique for optimal distribution of energy losses along the channel. A computer model was developed and was used to verify the methodology for flood flow and channel data at four locations.     

论煤矿安全长效机制中经济杠杆的作用

随着我国社会主义市场经济体制的进一步完善和国民经济的持续高速发展,安全生产也面临着新的挑战。在以煤炭生产为代表的高风险行业中建立“长久”而又“有效”的安全生产机制,必须坚持科学发展观,严格遵循经济规律,充分发挥经济杠杆作用。笔者结合我国煤矿安全生产的实际状况,从加强煤矿企业资本管理制度、实行煤炭资源有偿使用制度、建立税收优惠政策、强化煤矿安全保险制度、提高职工伤亡抚恤标准、推行煤矿负责人安全风险抵押金制度和实施煤炭行业人才培养体系改革等方面,提出了煤矿安全生产长效机制建设的新举措。     

江西省兴国县土壤侵蚀动态监测研究

介绍发应用遥感技术和调查资料编制的江西省兴国县三个时期（１９５８，１９７５，１９８８年）的土壤侵蚀动态监测图。结果表明，建国以来，该县水土流失的动态变化基本上呈抛物线的态势发展，目前水土流失面积在缩小，程度在降低，总的趋势向好的方向发展。