Alternative strategies for a father with a small brood: mate, cannibalise or care

Brood cycling, the alternation of periods of courtship and mating activity ("mating phase") with days of full brood care ("parental phase"), and total filial cannibalism, the consumption of all current offspring by a parent, have been interpreted as a response to the conflicting demands faced by parental males during the breeding season. Under the assumption that these two behaviours result from trade-offs among mating, caring and feeding, the strategy adopted by the male should depend on egg number and age. This hypothesis was tested in the scissors-tail sergeant (Abudefduf sexfasciatus), a common tropical damselfish. Observations of undisturbed males and a brood reduction experiment confirmed all theoretical predictions. The shift from the mating to parental phase occurred when an appropriate number of eggs had been obtained. When the brood was reduced on the first day of the parental phase, males often reverted to the mating phase, but never did so if the manipulation occurred on the second or third day. Only broods that were smaller than average were consumed by the parental male. Artificial reduction of the brood increased the incidence of total filial cannibalism, but the probability of cannibalism decreased with brood age. Electronic Publication     

高压脉冲放电处理焦化废水的研究

焦化废水中含有大量的氰化物,如直接排放将对环境产生很大的危害,本实验采用高压毫微秒脉冲产生的非平衡等离子体处理武钢焦化废水,分析了空气流量、SO2的质量浓度、放电时间等因素对实验的影响,放电之后发现当实验条件合适时,氰化物浓度可以降低90%以上,反应60min时则降低了93.93%以上。文章同时还探讨了放电等离子体去除氰化物反应机理。     

排污许可证制度在总量控制中的作用和地位

为了使污染物总量控制工作逐步走向深入并真正收到实效,对“排污许可证制度”核定单位的污染物排放量、排污行为的有效约束、企业排污权的转移与交易、区域污染物排放状况的调控,以及如何确立该制度在污染物总量控制工作中的地位进行了探讨。     

An improved product-process for cleaner chrome tanning in leather processing

Severe restrictions imposed by the pollution control authorities on the disposal of chromium, total dissolved solids and chlorides in tannery effluents have forced the tanners to look for low-waste, high exhaust chrome tanning salts. An improved chrome syntan with more than 90% uptake of chrome has been developed. The new product serves both as tanning and retanning agent and can be applied directly to delimed pelts thus eliminating the conventional pickling stage in the leather processing. This modified process helps to reduce the chemical oxygen demand (COD), total dissolved solids (TDS) and chlorides in the spent tan liquor by 51, 81 and 99%, respectively. The product offers full, soft leathers having shrinkage temperature comparable to conventional chrome tanned skins. Since the developed product is highly reactive, it saves time and reduces the water requirement when compared to the conventional chrome tanning method. Thus the novel product/process developed not only has advantages in reducing pollution loads but also seems to be techno-economically viable.     

总量控制区内功能区排放负荷的风频分配法研究

在总量控制A值法（GB／T13201－91）的基础上,考虑了总量控制区“气象资料”和各功能区位置及污染物“影响范围”等因素的影响,提出了“平均下风距离”的概念,从而建立了功能区排污负荷分配方法。通过与面积分配方法相比较,验证了新方法的合理性和有效性。     

微波消解预处理测定水和废水中总磷

提出一种用微波消解技术作为测定水和废水中总磷的预处理方法，这种消解方法只需10min即可，比用常规的高温高压消解法节省三分之一时间。用这身份种消解法对标样、地表水、海水、生活污水和工业废水样品进行了对比测定，所得结果经统计检验，两方法之间无显著性差异。对微波消解法的精密度和准确度进行了验证。     

水质等比例采样器在总量监测中的应用

介绍了水质等比例采样器在总量监测中的应用、配置及其在苏州市的使用试点情况，指出了水质等比例采校器在使用过程中存在着配置不足、对不同类型废水适应性不够、缺乏水样保存措施等问题，提出了环保部门可将水质等比例采样器的使用纳入污染控制管理的范畴，生产厂家应不断完善仪器性能，使用者必须接受专业培训，以及在仪器中设置低温冷藏室、加药系统和多个盛样器等对策。     

Response of organic carbon burial to trophic level changes in a shallow eutrophic lake in SE China

Lakes are an important component of terrestrial carbon cycling. As the trend of eutrophication in many lakes continues, the mechanisms of organic carbon(OC) burial remain unclear. This paper aims to understand the distribution of OC and the effect of trophic level changes on OC burial in Chaohu Lake, a shallow eutrophic lake located in the lower reaches of the Yangtze River, SE China. Two hundred and one surface sediment samples(0–20 cm) and 53 subsurface samples(150–200 cm) from the lake were collected.The OC accumulation rates(OCARs) are relatively low, with an average of 10.01 g/m2/year in the surface sediments. The spatial distribution of the OCARs is similar to that of allochthonous OC. The difference in total phosphate(TP) content between the surface and subsurface sediments(ΔTP) is significantly correlated with the autochthonous OC,suggesting that TP loading is a critical limiting nutrient for the lake's primary productivity.It is concluded that allochthonous OC is the dominant source of total OC in surface sediments compared to autochthonous OC. The primary productivity of Lake Chaohu increased due to increasing nutrient loading. However, the autochthonous OC contributed11% of the total OC in the surface sediments. This could be ascribed to strong mineralization in the water column or surface sediments.     

Stress,burnout and diminished safety behaviors: An argument for Total Worker Health® approaches in the fire service

Introduction: Firefighting is stressful work, which can result in burnout. Burnout is a safety concern as it can negatively impact safety outcomes. These impacts are not fully understood within the fire service. Further, the fire service needs support that safety strategies are needed to protect and promote the health and wellbeing of firefighters. Methods: Structural equation modeling was completed to examine a hypothesized model that linked stress and burnout to diminished safety behavior outcomes among a sample of career firefighters. Results: Findings support a full mediation model. Firefighter stress perceptions were positively associated with burnout and burnout was negatively associated with safety compliance behavior, personal protective equipment behavior, safe work practices, and safety citizenship behavior. Conclusions: These results illustrate the negative impact of health impairment on firefighter safety behaviors. Practical Applications: These outcomes suggest that interventions aimed at protecting and promotion firefighter health are needed. Total Worker Health® (TWH) approaches may provide the framework for these interventions.     

生物强化技术处理化纤废水

采用生物强化技术,即利用从废水中分离、筛选出的降解丙烯腈与总氰的特效菌株,使化纤废水加营养盐的培养基中丙烯腈降解率达98．7％,总氰降解率达84％。将分离到的特效菌株进行混合培养,其降解丙烯腈与总氰的最佳体积比为1．0：（1．5～2．0）。使用该技术不必改变化纤废水处理场原有工艺。